This is a hard one, considering all the bands i've seen and all the solo artists. For example, last month i've seen Marcus Miller and Tool. There's also a lot of bassists i haven't seen live, but would still get a place in my top 10 best bass players ever. Hmm... For now i'll stick with Justin Chancellor of Tool. That man puts his bass at the same hight of recognition in songs as Adam Jones does. (No offence, Adam Jones is a real good guitar player) Yep, Justin Chancellor it is!