You could write apps to run on the [Openmoko](http://en.wikipedia.org/wiki/Openmoko) [Neo FreeRunner](http://en.wikipedia.org/wiki/Neo_FreeRunner). The [Rasterman](http://www.rasterman.com/) used to work for them (some info is on his site about related work he's doing now).

Some more info about the platform is in [this fsf blog post](http://www.fsf.org/blogs/community/5-reasons-to-avoid-iphone...).