Alternatively, just get rid of the phone system entirely. Transitional points are starting to exist, and if we can do more things that interop without involving telecoms and are decentralized, you can have a situation a lot like what email /should/ be (with better identity management and less 60's holdover support).

I truly believe eventually cell phones will just be a data communications tool and "voice" will be done through these kinds of standards rather than phone numbers and ridiculous bureaucracy surrounding them, not to mention the quality of such communications will be fantastic comparatively.