Kaleidoscope is a multimedia fanwork exchange (fic, art, vids, graphics) hosted by dark_agenda for rare chromatic source fandoms. 20th Century Boys was nominated this year, which means you can request and offer fanworks for it if you sign up.
For more information, see: Official Announcement, Policies and Procedures | Frequently Asked Questions
To sign up, see: Sign-ups Announcement and Instructions | Sign-up Form | Countdown Clock for Sign-up Period | Current Sign-ups | Eligible Fandoms and Characters
Sign-up date: 2011 September 26th to October 8th, 9 p.m. Pacific Time (U.S.A.).
Due date: 2011 November 12th, 9 p.m. Pacific Time (U.S.A.).
Posting date: 2011 November 19th Pacific Time (U.S.A.).