you guys have mentioned all the greats, but I particularly love Miles Davis, Coltrane, Diana Krall, if you want more of a poppy feel, go for The Manhattan Transer. It's more vocal Jazz too so if you're in to that kind of stuff, feel free and another jazz group that I love, is Candela. They are a Japan based group, they performed at my highschool 5 years ago or so, anyway they use Japanese instruments, and its pretty great stuff. Marcus Miller is a bassist who has some good jazzy kinda stuff, as well as Victor Wooten, Wooten is more poppy but hey he does some good stuff. And if you appreciate music I think you'll like it.