Blackmar-Diemer is really fun, and crazy. But I wouldn't suggest the Ryder gambit: it only works on a certain type of player, and it's really hard to come back from that 2 pawn defecit.
I'm trying to learn the benko gambit, so I can't really tell you how that's working (but I've heard good things about it). As for the Sicillian, my worst upset was against the Smith-Morra gambit, the first time I'd really seen it used against me.
Against e5
king's gambit,
Scotch gambit / Danish gambit
Against scandinavian,
Blackmar diemar gambit ryder ganbit
Against sicillian
Smith Morra gambit