4chan
We've covered a lot of 4chan's activity on the internet at large, but as one commenter pointed out recently, there's a lot more to the site than the cyberbullying and trolling for which they've garnered press attention.

All the attention goes to 4chan's subforum /b/, a "no rules" board on which antisocial activity flourishes. They're largely responsible for the infamous attacks on Scientology from a few years back, and more recently the raid on the RIAA and MPAA websites. On this site I've covered /b/'s hack of the Time 100 list and their effort to send Justin Bieber to North Korea, among others.

Urlesque reader Thanquee wrote the following:
I DO wish people would stop calling /b/ 4chan. /b/ is only a part of 4chan - a large part, but only a part. There are many other boards like /tg/, /toy/, /fa/ and /fit/ (traditional games, toys and figurines, fashion and fitness)that I frequent that are much nicer than /b/ and don't go in for the whole 'HURR LETS RAID DEM FOR BEIN DUMB' schtick. I think it shouldn't be just /b/ that gets the spotlight either. /v/ (video games), for example, is a huge and fascinating community that I'd love to see given coverage.

I just hate it when people call /b/ 4chan because when I'm browsing /tg/ or something people ask what I'm looking at and then they smile knowingly 'Oh, 4chan' as if I'm immersed in this world of raids, fringe pornography and racism.

Thanquee's right. We often use the term "4chan" to describe the activity on /b/ because it's more familiar nomenclature, but it's unfair to lump the other 48 boards in with /b/. So that's why I've prepared this guide to 4chan's 48 lesser-known boards.

Be warned, even though most of the boards are safe for work, it's still 4chan. Be careful when clicking through, because even heavily moderated boards still host NSFW content now and then.

A word of warning: these images link to actual 4chan pages, which expire after a few days. Also, 4chan is full of nasty stuff, so be careful when clicking the images.
3D Modeling and Imagery
3D Modeling and Imagery
This worksafe board encourages users to post their best work and offer advice for beginning artists. It's a generally friendly board where designers share tips and show off their stuff.
Anime & Manga
Anime & Manga
4chan was originally conceived as a place for anime and manga nerds to talk about their hobbies. There are strict rules in place to ban people who spoil storylines.
Advice
A newer board, this is one of my favorite. It's like a crowdsourced advice column. Sometimes the responses are heartfelt and smart, other times hilariously snarky.

You'll find questions that range from, "How can I get past my shyness to talk to the girl I like in homeroom" to "I'm applying to art school and need to build a portfolio. What should I include?" to "What's this rash on my arm and how can I treat it w/o seeing a doctor?"
Animals & Nature
Animals & Nature
This board is for photos of plants and animals alone with discussion on how to care for pets and plants.
/b/
Random
This is the infamous anarchic board that spawns a lot of the trolling and cyberbullying on the web that you've read about here.
Anime/Cute
Anime/Cute
A place to post cute, rather than erotic, anime pictures.
Cosplay & EGL (Elegant Gothic Lolita)
Cosplay & EGL
This discussion board is for people who dress up like anime, video game or other fictional characters for fun. It's called cosplay (costume-play). An EGL is pictured here.
Food & Cooking
Food & Cooking
Another personal favorite. Share recipes, kitchenware deals and cooking tips. There's something special about the faux-macho culture of 4chan when used in the context of cooking.
Cute/Male
Cute/Male
Another anime board. This one's for posting images of cute male anime characters.
Comics & Cartoons
Comics & Cartoons
Here is a board for comics fans who aren't into Japanese animation. Western stuff only.
/d/
Hentai/Alternative
Hentai is hardcore pornographic animation. Weird fetishes like futanari (hermaphrodites!), bondage and tentacles are encouraged here. What do you want me to say?
/e/
Ecchi
Ecchi is the softcore alternative to /d/. Like, for if you just want to see a Kim Possible nip slip.
Fashion
Fashion
4chan's fashion board is surprisingly vibrant and full of stylish people you might not expect to even know what 4chan is. It's a place to talk about fashion trends, post images of your closet, and rate people's daily wear.
Fitness
Fitness
Physical fitness tips and photos of weight loss progress are just a few of the discussion topics you'll find on 4chan's fitness board.
Technology
Technology
Images of gadgets and tech from past, present and future. This one's less about discussion and more about eye-candy. Users often post photos of their "battlestations" (home computer setups featuring massive screens and gaming peripherals).
/gif/
Animated GIF
Animated GIF
A place to share animated GIF images, many of which happen to be pornographic, so beware.
/h/
Hentai
Yet another board for sharing hardcore cartoon porn. This board is based around more traditional hentai. Here you'll find stuff like pictures of Sailor Moon having sex with Princess Mononoke, which is what you really want after a long day at the office, right?
High Resolution
High Resolution
High-resolution 2D/3D artwork, scans, photography, and images. Mostly safe-for-work eyecandy.
International
International
A place to discuss global cultures and languages. There's also a lot of "England rulez America droolz!"
Otaku Culture
Otaku Culture
A place for Otakus (aka weaboos), people who have a passion for all things Japanese to share photos of their Hello Kitty Backpacks and Pocky.
Weapons
Weapons
This is where gun nuts, military history aficionados and guys who inexplicably own seven samurai swords gather to talk about things that shoot, chop, stab and explode.
Literature
Literature
I find this to be one of the most enriching boards. It's a place to talk about books. While a lot of the discussion centers on sci-fi/fantasy and Ayn Rand fandom, there is some surprisingly smart cultural commentary to be found on this board.
Mecha
Mecha
You know Transformers, right? Well imagine a world where that's barely scratching the surface of bipedal humanoid robots, robotic exoskeletons and the like. You live in that world.
Music
Music
Another favorite. This is a place to talk about your favorite music, but more importantly, make fun of others' favorite music. The discussion here can approach Pitchfork levels of snobbery. Other threads are just full of lonely death metal fans.
Transportation
Transportation
"Trains, planes, ships, bicycles, flying elevators-post 'em all!" reads 4chan's description for this board.
News
4chan's News board is special because they are so quick to share breaking news. If you spend much time lurking here you'll often be the first among your friends to hear about some stories. And then people will respect and envy you.
Auto
Auto
A place to share photos of cars, and occasionally engage in car talk.
Photography
Photography
A place to post only photos that you have taken, along with a description of where and when the photo was taken along with a description of the camera used and any other useful information.
Papercraft & Origami
Papercraft & Origami
A board dedicated to the art of folding paper so it looks like stuff. 4chan founder Chris "Moot" Poole says this is one of his favorite boards.
Request
Let's say you saw a photo of something somewhere years ago and you just have to see it again. Or maybe you're looking for an obscure foreign movie you saw once but can't remember the title. Ask here. Moderators try to cut down on piracy, but it happens.
ROBOT9000
One of the most fascinating boards. Based on a post written by XKCD's Randall Munroe, this board attempts to eliminate annoying copypasta, spam and generally unoriginal content by employing a bot affectionately called Robot9000 to automatically delete any content that has ever appeared on the board before.

In the words of Munroe:

There would be no "all your base are belong to us", no "lol", no "asl", no "there are no girls on the internet". No "I know rite", no "hi everyone", no "morning sucks." Just thoughtful, full sentences.

And it seems to work, to some extent. The content is notably more sophisticate than the anarchy on /b/.
/s/
Sexy Beautiful Women
Another porn board. This one is at least free of fetishes and hardcore stuff. Just tasteful nudes.
Science & Math
Science & Math
Nerds talking about science and math. Simple enough. Kids who try to post their homework are banned, which is hilarious.
Sports
Sports
Even some computer nerds like to talk about sports. A lot of the discussion is devoted to really obscure stuff like curling though, which suggests that it's less about sports fandom and more about sports curiosity. Also a lot of "LOL European football is the best. American football sucks moar like handegg!"
Torrents
A place to share links to torrents of pirated content.
Traditional Games
Traditional Games
Board games, paper games, war games, card games, etc. go here! This is another of Chris Poole's favorites.
Toys
Toys
Just a place to talk about toys. Mostly action figures and the sort of collectibles so expensive no actual kid would own them.
Travel
Travel
A place to ask questions about other cultures, tell stories about places you've traveled and talk about the best things to see and do across the globe.
Television & Film
Television & Film
A place to talk about TV and film, as well as media production and gossip.
/u/
Yuri
Yet more porn. This one's for softcore animated images depicting two or more women.
Video Games
Video Games
Often called "Vidya," this board is for gamers who want to talk about games.
Pokémon
Pokémon
Pokémon fans talking about Pokémon.
Anime/Wallpapers
Anime/Wallpapers
A place to post high-resolution, large anime or J-pop related images intended to be used as desktop wallpapers.
Wallpapers/General
Wallpapers/General
Any high-res desktop wallpapers that aren't anime-related go here.
/y/
Yaoi
Yaoi is a A Japanese term for homosexual male fan-fiction. This board is dedicated to sharing images related to erotic images of anime dudes.
Paranormal
Paranormal
A place to share stories about aliens, monsters and creepypasta, which are commonly copy-pasted spooky stories that circulate around 4chan.
Oekaki
Oekaki
A place to share your own drawings, based on the Japanese word for "to draw."
Artwork/Critique
Artwork/Critique
Another board for sharing your art, not necessarily drawings.
Flash
Flash
A place to upload flash files pertaining to Japanese culture.
Rapidshares
A place to post Rapidshare (a file hosting website) links. Mostly used for sharing pirated music, movies TV shows, etc.