Lost mediaLost media is any type of media thought to no longer exist in any format, or for which no copies can be located, partial or otherwise.3 min / Deep Max Headroom signal hijackingsOn November 22, 1987, two television stations based in Chicago, Illinois, were hijacked two hours apart from one another by unidentified perpetrators.3 min / Deep Internet Mysteries: 11B-X-137111B-X-1371 is a 2015 viral video sent to GadgetZZ.com, the Swedish tech blog that publicized it.3 min / Deep 2012 phenomenonThe 2012 phenomenon was a range of eschatological beliefs that cataclysmic or transformative events would occur on or around 21 December 2012.3 min / Deep Anonymous (hacker group)Anonymous is an international collective, organized as a decentralized group of activist and hacktivist individuals, best known for orchestrating cyberattacks against governments, government institutions, agencies, corporations, and the Church of Scientology.3 min / Deep Ben DrownedBen Drowned (originally published as Haunted Majora's Mask Cartridge) is a three-part multimedia alternate reality game (ARG) web serial and web series created by Alexander D.3 min / Deep Internet Mysteries: BitcoinBitcoin (abbreviation: BTC; sign: ₿) is the first decentralized cryptocurrency.3 min / Deep Blue Whale ChallengeBlue Whale Challenge (Russian: Си́ний ки́т, romanized: Siniy kit), also known simply as the Blue Whale, is a social network phenomenon, first appeared in Russia in 2013, that is claimed to exist in several countries.3 min / Deep Candle CoveCandle Cove is an online creepypasta horror story written by web cartoonist and author Kris Straub.3 min / Medium Celebrity Number SixCelebrity Number Six (sometimes abbreviated C6) is the name given to a previously unidentified face on a fabric print, the subject of a years-long online search.3 min / Deep Cicada 3301Cicada 3301 are three sets of puzzles posted under the name "3301" online between 2012 and 2014.3 min / Deep Internet Mysteries: ConfickerConficker, also known as Downup, Downadup and Kido, is a computer worm targeting the Microsoft Windows operating system that was first detected in November 2008.3 min / Deep Dead Internet theoryThe dead Internet theory is a concept that asserts that the Internet consists primarily of bot activity and automated content manipulated by algorithmic curation.3 min / Deep Internet Mysteries: ElsagateElsagate (derived from Elsa from the Frozen franchise and the -gate scandal suffix) is a controversy surrounding videos on YouTube and YouTube Kids that were labelled as "child-friendly" but contained themes that were considered inappropriate for children and younger audiences.3 min / Deep I Love BeesI Love Bees (also known as ilovebees or ILB for short) was an alternate reality game (ARG) that served as a real-world experience and viral marketing campaign for the release of developer Bungie's 2004 video game Halo 2.3 min / Deep Internet Mysteries: ILOVEYOUILOVEYOU, sometimes referred to as the Love Bug or Loveletter, was a computer worm that infected tens of millions of Windows computers following its release on 4 May 2000.3 min / Deep Internet OracleThe Internet Oracle (historically known as The Usenet Oracle) is an effort at collective humor in a pseudo-Socratic question-and-answer format.3 min / Deep John TitorJohn Titor and TimeTravel_0 are pseudonyms used in communications and on Internet forums between 1998 and 2001 by an individual claiming to be an American military time traveler from the year 2036.3 min / Deep Local 58Local 58 is a horror web series created by American cartoonist Kris Straub.3 min / Deep Internet Mysteries: LulzSecLulzSec (a contraction for Lulz Security) was a grey hat computer hacking group that claimed responsibility for several high profile attacks, including the compromise of user accounts from PlayStation Network in 2011.3 min / Deep Marble HornetsMarble Hornets is an American found footage web series created by Troy Wagner, Joseph DeLage, and Tim Sutton.3 min / Deep Momo Challenge hoaxThe "Momo Challenge" was an internet hoax and urban legend that was rumoured to spread through social media and other outlets as a creepypasta.3 min / Deep Mt. GoxGox was a bitcoin exchange based in Shibuya, Tokyo, Japan.3 min / Deep Ong's HatOng's Hat is one of the earliest Internet-based secret history conspiracy theories.3 min / Deep Internet Mysteries: PetscopPetscop is a YouTube horror web series by Tony Domenico, made to resemble a YouTube Let's Play series.3 min / Deep Polybius (urban legend)Polybius is an urban legend about a mysterious arcade video game.3 min / Deep Project ChanologyProject Chanology (also called Operation Chanology) was a protest movement against the practices of the Church of Scientology by members of Anonymous, a leaderless Internet-based group.3 min / Deep Satoshi Nakamoto31 October 2008 – 26 April 2011) is the name used by the presumed pseudonymous person or persons who developed bitcoin, authored the bitcoin white paper, and created and deployed bitcoin's original reference implementation.3 min / Deep Silk Road (marketplace)Silk Road was an online black market and the first modern darknet market.3 min / Deep Slender ManThe Slender Man (also called simply Slender Man, Slenderman, Slender, or Slendy) is a fictional supernatural character that originated as a creepypasta Internet meme created by Something Awful forum user Eric Knudsen (using the pseudonym Victor Surge) in June 2009.3 min / Deep Internet Mysteries: StuxnetStuxnet is a malicious computer worm first uncovered on 17 June 2010 and thought to have been in development since at least 2005.3 min / Deep The BackroomsThe Backrooms is a fictional location invented in a 2019 thread on the imageboard website 4chan.3 min / Deep This ManThis Man, often called the Dream Man, is a conceptual art project and hoax created by Italian sociologist and marketer Andrea Natella.3 min / Deep Time CubeTime Cube was a pseudoscientific personal web page set up in 1997 by Otis Eugene "Gene" Ray.2 min / Medium Toynbee tilesThe Toynbee tiles, also called Toynbee plaques, are messages of unknown origin found embedded in asphalt of streets in about two dozen major cities in the United States and three South American cities.3 min / Deep Internet Mysteries: UsenetUsenet (), short for User's Network, is a worldwide distributed discussion system available on computers.3 min / Deep Internet Mysteries: UVB-76UVB-76 (Russian: УВБ-76; see § Name and callsigns for other callsigns), also known by the nickname "the Buzzer", is a shortwave radio station that broadcasts in upper sideband mode on the frequency of 4625 kHz (wavelength of 64.8 m).3 min / Deep WannaCry ransomware attackThe WannaCry ransomware attack was a worldwide cyberattack in May 2017 by the WannaCry ransomware cryptoworm, which targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the form of bitcoin cryptocurrency.3 min / Deep Polybius (urban legend)An alleged arcade game became one of the internet's favorite cabinet myths.7 min / Easy Max Headroom signal hijackingA strange masked figure interrupted Chicago television broadcasts in 1987.7 min / Easy The BackroomsA liminal image and short caption grew into a collaborative horror mythology.7 min / Easy Slender ManAn internet-born figure spread from forum images into fiction, games, and crime reporting.8 min / Medium Webdriver TorsoA mysterious YouTube channel posted thousands of abstract test videos.7 min / Easy UVB-76A Soviet-era shortwave station has broadcast a persistent buzzing signal for decades.7 min / Easy Numbers stationShortwave broadcasts of voices and codes suggest old-school espionage in plain hearing.8 min / Easy 11B-X-1371A viral video full of plague imagery and coded messages invited crowdsourced decoding.7 min / Easy Local 58An analog horror web series turns public-broadcast aesthetics into cosmic dread.7 min / Easy PetscopA fictional unreleased game unfolded as a long-form YouTube mystery.7 min / Easy Marble HornetsA web series helped shape found-footage horror on YouTube.7 min / Easy This ManA dream-figure hoax spread through forums, posters, and viral sharing.6 min / Easy John TitorA forum poster claiming to be a time traveler became a lasting internet legend.7 min / Easy Time CubeA notorious website presented an idiosyncratic cosmology in dense, unforgettable prose.6 min / Easy Satoshi NakamotoBitcoin's pseudonymous creator remains one of the internet age's biggest identity mysteries.8 min / Medium BitcoinA cryptographic currency experiment grew into a global financial and cultural force.9 min / Medium Silk Road (marketplace)An online black market forced new questions about anonymity, law, and cryptocurrency.9 min / Medium Mt. GoxA major bitcoin exchange collapsed after hacks, losses, and accounting failures.8 min / Medium UsenetA pre-web discussion system shaped online communities, culture, and archives.8 min / Easy Internet OracleA playful question-answer service became an artifact of early internet culture.6 min / Easy Project ChanologyAn online campaign against Scientology marked a turning point for Anonymous.8 min / Medium LulzSecA short-lived hacking group became infamous for high-profile breaches and showmanship.8 min / Medium Morris wormAn early internet worm revealed how fragile networked systems could be.8 min / Medium ILOVEYOUA worm disguised as a love letter caused global computer disruption.7 min / Easy ConfickerA resilient computer worm infected millions and sparked international response.8 min / Medium WannaCry ransomware attackA ransomware outbreak exploited leaked tools and disrupted systems worldwide.8 min / Medium ElsagateDisturbing videos disguised with familiar children's characters exposed weaknesses in recommendation and moderation systems.9 min / Medium Momo ChallengeA sculpture's image became attached to a viral moral panic about an online challenge that evidence could not substantiate.8 min / Easy I Love BeesA damaged-looking website unfolded into an alternate reality game promoting Halo 2 through calls and hidden clues.8 min / Easy Ong's HatA fictional conspiracy spread through photocopies, bulletin boards, and early online communities as an immersive legend.8 min / Easy Perplex CityA global puzzle hunt mixed collectible cards, websites, live events, and a cube hidden somewhere in the real world.8 min / Easy StuxnetA highly sophisticated computer worm sabotaged Iranian nuclear centrifuges while concealing its effects.10 min / Medium GhostNetResearchers uncovered a cyberespionage network that had infiltrated government and diplomatic systems around the world.8 min / Medium Toynbee tilesCryptic linoleum messages embedded in city streets inspired decades of documentation and theories about their creator.8 min / Easy