Futurama

Planet Express Employee Lounge

English Futurama message board; thousands of members. Lots of activity and debate.

Independent Simpsons and Futurama Forum

Russian message board, very active; has a section for The Simpsons and one for Futurama.

Felizonia

Spanish Simpsons forum with an active Futurama section.

Der Hip Joint

German message board. Lots of members though the Futurama-related activity is severely limited. Backed by several sites.

Rough Draft Studios Test Site

Rough Draft Studios, the animation studio behind Futurama, has a message board with a Futurama section frequented by the directors and animators (some of them even answer questions from fans, if you ask them nicely).

alt.tv.futurama

Google Groups archive for the Futurama Newsgroup. Several hours behind the Usenet servers; if you have a newsreader configured, click here instead.