Beezer,
Run, don't walk to your patent attorney. You're going to buy Cam's boat to use as a tender when you're done with this.
You have to patent the concept of cellphone credits, or at least a variety of names depicting same. It will be the same as carbon credits in practise. Think of it!!! One of the huge marketing ploys with cellphones is that they make you important. Remember when only doctors had pagers and then phones? Everybody else got 'em because, when they went off in the movie theater, everybody else knew they must be somebody important. You're going to bring that all back, times ten. Cellphone credits will run thousands of dollars a month and the truly important in their own mind will willingly pay. The actually important, like those doctors, will just have to get in
line.
Beezer-YOU'RE GONNA BE RICH!!!! (can I play with the stereo on your new tender?)