From WhatPort80

Chan could refer to many things:

1. A popular Chinese surname (Chinese 陳; simplified Chinese 陈) in Cantonese transcription. The Mandarin transcription of the same name is Chen (surname)
2. Ch'an （chi. 禪) (pinyin: chán), a sect of Buddhism cognate to Zen in Japanese Language.
3. A Japanese honorific (like san) used to refer to children, girls and young women, which is where most of the following references draw their inspiration from for one perverted reason or another.
4. 2chan - The father of all *chans
5. 4chan - The mother of all english *chans
6. 7chan - A site that wants to be 4chan
7. Desuchan - A site for Desu fans. (Currently ALIVE DESU)
8. 04chan - The new /b/
9. 31chan - Duizendpoot in mijn Nederlandse Chan
10. 204chan - A site that wishes it was a little girl
11. 1chan - A great site about trains.
12. 5chan - A site for Furries.
13. 12chan - A site for pedos.
14. 722Chan - A site for pedos and furries
15. ##chan - you don't talk about ##chan
16. not4chan - A site for pedophiles.
17. Charlie-chan - An ancient "Chinese" detective; counter to Fu Manchu but still pwoof of dweadfull wacism
18. Jackie-Chan - Popular Kung Fu expert and fail actor.
19. Britchan - British based chan.
20. 666chan - A chan made by AtlantisIRC lusers.
21. NotFourChan Lolicon and tentaclats.
22. Combat Chan New /b/ cancer site and base for traps and raiders.
23. 915chan Patriotic Nigrachan. Also no furries allowed.
24. ChristChan A website made by some /b/ christians for half-serious half-trolling fun.
25. 28chan A *chan for pseudo-intellectuals.
26. egochan A new website that is still new.
27. 55chan Brazilian chan made of cancer and fail.
28. Hurrchan A new chan made of traps, faggotry, transsexuals, and desktop threads.