A pimp disc is a CD or DVD full of
fanfiction, fanart, character info,
story info, etc of a specific fandom. They are used to encourage
people to join that fandom.
Mary: Anne sent me a pimp disc of 'Prince of Tennis' last night.
Ella: Oh, I've heard of that
anime. Is it good?
Mary: Well, the disc had the first episode and some fanfiction, and it looks pretty cool. I think I'll ask for the box set for
Christmas.