We are going to Coldplay concert next week and when I bought tickets, I had somehow managed to buy an extra ticket on other side of the stadium. I had forgotten about it until I saw it few days ago. Used the ticketmaster service to put it on sale & was not expecting to go - i mean who buys a single ticket to concert? Well, turns out it sold in half a day! Made a small profit also in the process. Glad I remembered about this lone ticket.