I spend my life around the damned things developing embed software, middleware and applications (games).
The best device ever made was the Nokia 6310i - 7 days battery life. They all use virtually the same hardware. If you want to use it for something other than a phone then:
iPhone for apps
Blackberry for email+battery life (you can remove the "sent from by etc etc" line)
Android to be a geek, live home screen & maybe apps
Samsung Wave for, 1ghz cpu
Nokia, the 12mp camera
Palm Pre, for some reason