Because retro is apparently the new futuristic, here is the cell phone of the future, the Sparkfun Electronics Port-O-Rotary. The company retrofits the old phones with all the necessary electronics, so all you have to do is add your SIM card and you're good to go. The rotary dial works for outgoing calls, and incoming calls ring the actual bell style ringer. They claim battery life is good for 4-5 days on average, which isn't too bad. The cost is though, at $499 ($399 if you buy 100 or more), it's an expensive personal communications device. But none of that really matters, all that does is that now you can talk dirty to your girlfriend on a rotary phone whenever you want without your mother picking up the line in the kitchen and screaming at you.
Rotary Cell Phone Is Awesome [gizmodo]