I’m sure a lot of people will appreciate this
http://www.friendlyarm.net/products/mini2440
It’s almost like a DIY smartphone-minus-phone for $110, you can buy the Wifi and camera module for it separately and they are pretty much plug-and-play
It’d be so easy to hook a GSM module up to this, it even has a mic on board, you can pretty much buy the eval board for the Telit modules and connect less than a dozen wires and it becomes a DIY smartphone