So I've noticed a lot of individuals looking to make some extra money have started reselling sporting event or concert tickets online for a profit. It appears to me that they simply buy from Ticketmaster (since they essentially have a monopoly on ticketsales) and resell them for a profit on StubHub, Ebay or Craigslist.

Does anyone have experience doing this? It's risky to know which events will sell out and profit but I've done it on a few UFC events just to "test the market" and I've done quite well. Any advice, experiences, tips?

Steve