SeatGeek - A ticket-price tracker. Think stock market index for ticket prices, that find some sweet deals. It's a newly developed company and says their ticket tracking capabilities are about 80% accurate--making sure you don't overpay for good tickets. They compare every major (and a few minor) ticket retailers to find and rate deals, depending on how much of a steal it is. My favorite feature is the Geekdeals, although I've only seen them come up a couple times on the right side of the search criteria. Two lower-level Suns tickets for 16% off, about $58 each. Not too shabby, plus the site is designed well and you dont need to sign up to look around (finally).
All in all, worth checking out if you're about to buy any pair of tickets.