How will the radar screens round the country look with all this new information flashing up?
We could have a new GA sport; TCAS alerting. Let's all fly along the base of airways, mingle round beacons and see how much TCAS related disruption we can cause.
I suppose, if they have a legally enforceable way of noteing when we are in the air and where they could introduce a tax sytem that charges for being airborne, with differing rates depending on where you are, £1 a miniute in rural Cambridgeshire, changing to £5 a minute through the Manchester low level corridor. Would be easy with computerised recognision, billed automatically using a/c registration details on another computer.