Panther works wonderfully on my b/w 400mhz. It has been modified by adding gig of ram and a 32meg ATI card. It even pulls of expose but not as well as a G4 would of course. I have started an Panther list at my site http://void.callthegeek.com My goal is to get beta testers to help out those that want to get into Panther on older machines. I also wrote a full review on its performace thus far.

Hope this helps.