Fanfics Addicts Anonymous.
Seriously, writing (and reading) fanfictions is a big part of my day! I'm always on fanfiction.net. In fact, I'm probably on it too much!
I'm writing fanfictions for X-Men, Four Brothers, Harry Potter (present and past), Star Wars, Supernatural, Smallville, ALIAS, Roswell, and a bagillion more!
One of the best fanfictions I've EVER read is by GatherYeRosebuds and is a 3-part x-Men series entitled "In Her Glory", "The Promise Broken", and "Last Words". Each part is five chapters long, five chapters of complete wonder! If you love fanfics and you love X-Men, GO READ THIS!!!!
Also, if you're interested... http://www.fanfiction.net/~secretsbeneathmysoul