I dont, but I can tell you that I LOVE my imac...so if it were me, I think I'd go for the ibook. I guess the best thing to do is look at the memory the generation (g4 or g5) and various other features.....do you need access to a printer? what about batteries? Personally, I am glad to see another apple fan, I think they are superior to pc's and pc clones since they arent subject to any of the pc viruses or worms!
EDIT:
oops the Powerbook looks like the better deal........go for the Powerbook!