I discovered Rufus Cappadocia, a Canadian born jazz cellist, a while back cruising through YouTube videos on electric and jazz cello. His techniques, range from percussive strumming and plucking to melody lines taken from the Middle East and elsewhere, extend the range of what the cello means very considerably. I'm listening now to Transformation, off his solo cello album, and it is extraordinary - you would have no idea you were listening to a cello. It sounds like he is strumming a bass guitar of some kind combined with some kind of drum. He plays a self designed five string electric cello, with an extra bottom string on the low F. The instrument is electric but, as he says, the electronics are passive in order not to lose the overtones lost by other electric cellos (including presumably my Yamaha). I also rather liked this YouTube video of him with vocalist Bethany - he plays entirely by plucking, making his cello into a percussive, driving instrument. Here on youtube. I don't know much about acoustic jazz upright bass, but watching him play, it looks an awful lot like he's studied how upright bass is played, how the right hand is used, very loose, almost slapping the strings.