One of the first business idea posted on Founders Basecamp was aiming at helping people cash in on their Loyalty Miles. Remember, there are more Airlines Miles than US dollars in circulation, but most of them go un-used.
A lot is broken in these "loyalty" programs, but I got to witness even worse last week as I started investigating businesses specialized in customer acquisition via "cashback" programs. They simply are not effective for brands in the long run, as they attract deal chasers who'll leave as soon as your competitors will offer a better deal.
What got me interested is that they attract A LOT of customers. For ex the Taste Card in the UK has +1 million customers paying 40£ per year.
That got me thinking of a combination of both. Remove that 40£ upfront fee, add the existing but unused loyalty incentives (e.g. Retailer vouchers, Airlines miles), and what do you get?! A marketplace like Airbnb, where you'd sell your vouchers/miles, so buyers can get the ones they want, when they need it.
Let me know if you are interested to work on this one and I'll connect you with the working group OK? And bring along like minded friends if you fancy.