Buy & Sell Waiting Time
Time is money, but for different individuals it has a different value. Bill Gates for example (or a busy manager) will lose hundreds of dollars in the doctor's waiting room or while he is standing in a long queue at the supermarket, while a student's time is much cheaper.
My idea is that you should be able to buy / sell your waiting time. If you're in a hurry and don't want to lose valuable time, you should be able to buy time in situations that would otherwise be time-consuming. Selling their time would also be an interesting source of income for people who are not so well off.
Of course, some (central) agency would probably have to coordinate this.