Muse - Chris Wolstenholme, these guys put on some really spectacular shows live, great stage props and effects, and they ALWAYS sound great and have such a high energy.
Rush - Geddy Lee, don't know that I need to say much more... Haha, but they are so great live, even 40+ years later, and Geddy's bass play is phenomenal.
Bela Fleck and the Flecktones - Mr. Victor Lemonte Wooten, my personal favorite and the band I would follow around the world if I had the money. I mean Wooten alone is enough reason, but their shows are soooooooooo amazing. Each musician is quite debatably the best in the world at their instrument and it shows. They play unbelievably together, and you're pretty much assured moments of humor, deeply musical and emotionally connected music, maybe a bass flip or two, and your jaw hitting the floor a few thousand times... Everyone, bass player or not should see these amazing musicians!
Others to note: the frames, the swell season, eagles, pearl jam, hall & oates, and a bunch more I'm sure I'm forgetting that deserve mention...