I'm a big fan of tort pickguards with black. Mint green is pretty cool, too. I actually just saw a Shecter bass that was black with an orange pearl pickguard and truss rod cover. It was very "look at me," but I thought it was really cool. Makes me want to go with a green pearl on one of my black basses...
Spectorbassguy--THANK YOU for that great pic of an Abalone pickguard. I went with Abalone with white for my new Bongo fretless without having seen a really good example of it. That great shot of your fretless makes me even more excited about it!