Sometimes I miss my N-Gage. Not in comparison to modern phones, but mostly for what it let you do at the time.
In a market where people buy a $600 iphone, i'm sure something of the ngage's price point would break the bank.
Certain bluetooth controllers work with some Android games or emulators, and sometimes they can be attached to the phone so that it feels like a normal handheld. It just needs to be adopted more.
The N-Gage comes to mind... Urgh.
the games sucked, but it was a good idea. if only someone like, nintendo for example could do it right.