Author has written 6 stories for Wheel of Time.
You know, I love fanfiction. It's like a warm, fuzzy, slightly chewed security blanket, just the thing to help you relax after a stressful day.
The only fandom I've written in is the Wheel of Time, a looooong fantasy series by now-deceased author Robert Jordan. I love it because its has the most incredibly detailed worldbuilding, numerous simultaneous plots and an extremely innovative, yet almost logical, system of magic. Writing fanfiction for it, however, is a nightmare - the plots are so tightly woven and so closely interlinked that the usual fanfiction question of 'what if' is extremely difficult to address.
Other fandoms I'm into at the moment. Hm. Star Trek, always. If fanfiction has history, Star Trek is it. The sheer open-ended possibility of those shows made it a fanfic-writer's paradise (and apparently Hollywood agrees: the Reboot was a classic AU). Also, reading stories written in plaintext always makes me nostalgic for more innocent times, when the internet was made of dial-up.
Stargate: Atlantis is a true puzzle, for it sucks, and sucks a lot. The plots are ludicrious, or simplistic, or both, the science is brain-breakingly awful, and the less said about the characters, the better. However, like Star Trek, its premise was incredibly open-ended (really. don't let little things like plausibility or the laws of physics get in the way of your story - the writers sure didn't) and resulted in an explosion of creativity. There are some ridiculously good stories in that fandom.
I wish there was more fanfiction for The Dresden Files, the books. Mystery, wizardry and fun characters don't often some so conveniently bundled together.
The first three series of Criminal Minds are astonishingly good. I could write for a page and a half on why, but basically, it boils down to the fact that it's subtle, and multilayered, and doesn't treat the viewer like an idiot.
Recently the Danish crime serial Forbrydelsen became very popular in the UK. While not quite as suicidally depressing as The Wire, it's still fairly bleak. I love it because every single character is so very human. Not always likeable, but always real.
On a fluffier note, I really like White Collar. There's not a lot of depth to it, but the scripts are witty and the characters are fun. The sweetest, most adorable, most perfect marriage I've ever seen on a television screen is in that show, the perfect tonic after a long day. Also, and I say this as someone who does not do the slashgoggles thing, there physically could not be more OT3 subtext in that show.
The first time I watched Firefly, I hated it. I thought the acting was wooden, the dialogue painful, the premise clichéd and the characters unengaging. So I have no idea why I gave it a second chance, but I am very glad I did. See, the thing about Firefly is that it's brilliant in the same way a plain, austere room can be beautiful. It is minimalist almost to the point of its own nonexistence. You might even say it's a series of stories told in metaphor, and it can pack more meaning into a paragraph of dialogue than most other shows manage in an entire episode. It is measured, restrained, unassuming and low-key. And very good.
Lastly, Dead Set. The premise of this little miniseries is pure crack - zombies in the Big Brother house. It ought to be funny. It's not. Do not watch alone, or in the dark.