Flash

There's 4 flash trends that existed on the 00s. In addition, we need to look at a site closely related to Flash & Internet Culture and Japanese flash animation.

Newgrounds
Newgrounds became the headquarters of flash animation from 2004 to the end of the 00s. It was massive (at least for the time) and harbored all kinds of ideas on flash animation and programming. Most iconic flash content was made on Newgrounds, among them parodies, porn games, long and often unfinished animation series and ambitious game projects. The themes touched Newground's by content were many, but the most common where edgy shorts with black comedy and nu metal music, gamer, nerd & furry animations and references (and drama), Newgrounds-born things like the clock legion and self-referential content like the entries for their myriad mascots. During it's earliest days Newgrounds used to create animutations, but they quickly went out of fashion. The atmosphere at the site could be described as "teenage", a place where many people had their first experience with the nerd fandom, animation and Internet communities.

Something Awful, Albinoblacksheep and other websites
http://www.somethingawful.com/flash-tub/

Something awful's and albinoblacksheep come from the same cultural roots than Newgrounds. However their influence peaked in the early 00s and entered rapid decay. SA was not a flash HQ, albeit it did host it's own flash archive, it's safe to generalize that all flash artists of this trend had an account of SA. One of the most notorious - and classic - works were animutations, early, cheaply done flash works that used static pictures and made videos out of them. Albinoblacksheep has most classic animutation works around. Other content was humouristic in nature, eschewing epic stories and the edgy content of Newgrounds in favour of nerd comedy and simpler animation. Many animators ended up becoming Internet celebrities like Niel Cicierega (Lemon Demon).

4chan's /f/, swfchan,com, dagobah.net, gnomeparty.com, bimmy.org, z0r.de and others
(The first two are covered in field research)

Flash portals of 4chan pedigree. While they don't directly associate with the site and bring content from all flash communities and "trends" that are still alive, all these sites are children of 4chan /f/'s culture. Effectively "underground" flash compared to Newground's animation portal or the dying flash game sites (thanks free2play) it came to rise around 2005 when 4chan's /f/ began to distinguish it's content and culture from the content they imported from 2chan's /f/ board. Being constrained by a very limited file size led to creative use of assets. By far, /f/'s most distinguishing feature is the music loop. Grabbing a simple .gif or video clip and looping it with music. Other examples are hacked flashes where users would change assets and graphics, crudely animated parodies, cleverly programmed music players or flash compendium where they try to put as many references in a single file as possible. Due it's imageboard nature /f/'s flash culture has no taboos and will happily post ambient, comfy and experimental flashes (one of the few sites to appreciate the truly bizarre) works next to anime hentai loops. Another thing with /f/ is that content is very hard to source unless the name of the creator is embedded in the flash. From an outsider's experience 4chan, Dagobah and z0r.de are essentially mysterious sites hosting strange, hard to source yet amusing content not found elsewhere on the net, and the odd uncomfortable thing. If you think it's similar to YTMND's culture, it's no coincidence. YMTND shared userbase with 4chan for most of it's golden age and drew similar aesthetics and humour, albeit less raunchy. We owe all we know about /f/ to swfchan's archive.

2channel and 2chan's /f/
The father's of 4chan's flash culture. It is different in many aspects. 2channel's flash animators are very fond of a particular aesthetic that resembles' their SJIS emojis (in the form of literally emoji faced, featureless paint-white men), amateurish songs made by them, moving ASCII and SJIS versions of their characters and a light, upbeat form of comedy that's practically their trademark. Japanese flash culture excels at music videos and displays of tenderness. They will grab a full song - often of their own making, and animate from beginning to end. One of the most iconic 2chan (or was it 2channel? can't remember) exports was There She Is!, a series of animated songs depicting the amorous adventures of a cat and a rabbit. In a way, these music videos could be seen as the influence that gave birth to the western music loop. I don't know how different 2chan's content is to 2ch, if I'm not mistaken most otaku swf content imported from Japan is from 2chan, rule of thumb: If there's anime, chances are it's 2chan. Unfortunately I know jack about their websites and flash portals so we'd need to research this before archiving anything.

YTMND
You're The Man Now Dog is not specifically a flash site. It uses html assets to load music and animations and presents it with a non-interactive loop. Some sites do make use of Flash content though. Culturally, however, it draws a lot from animutation-era SA and 4chan's flash culture (YTMND and 4chan descend directly from SA, in fact). Irony and parodies are in abundance, and due to their non-conventional content creation method their works are small-sized. It's still recommended to archive them, as YTMND was extremely influential in the mid 00s