My gaming group has been playing Traveller lately using the D20 version. We're having fun, but the ruleset doesn't always seem a great fit to the setting, but we hand wave a bunch of stuff and leave it to the GM to figure out the details when needed. However, I've always like the original Game Designer's Workshop version and I have the GURPS version as well (although I've never played it). Character creation is a mini-game unto itself! There's something special about dying before your character is ever created (missing from the GURPS version). Anyone play Traveller and have a favorite version?