Exchanging minutes...

My last post about "mobile money" made me think about the whole process of mobiles and currency.

Have any operators thought about letting users exchange or sell minutes from one phone to another? It must be quite common to find a group of friends on pre-pay packages and one of them runs out of credit and needs a quick top-up. Why not let them get their minutes from a friend?

Furthermore, given that mobile minutes are such an essential currency for everyone these days, why not allow minutes to become a tradeable currency? Perhaps on websites, incentives could be offered to users by topping up minutes on their phone. I need to speak to my operator CFO friend to see if this makes financial sense. I'm sure he could see the financial benefits, if there are any.