I'm sure you're familiar with sites like Priceline and Orbitz to get discounted airline tickets. Here is a neat site that lets you search several of these sites at once. It's called Yapta.
With Yapta, you search for tickets as usual. However, it can pull prices from different places. This includes sites like Orbitz, Expedia and Priceline.
There are also extensive filter controls. You can easily modify settings to get desired ticket prices. Yapta will even e-mail you when prices drop. What a great way to save time and money!
How handy is that?