Do you have a parking space not being used at a certain time of the day? Well, you could be sitting on a small pot of gold, as some people would gladly fork over cash for the chance to use it while you're away. Currently available in Baltimore, D.C., and San Francisco, and more soon to come, the Parking Panda app for your iPhone allows you to do just that, while simultaneously allowing parking garages to offer discounts when their lots aren't full. If that's not quite enough to convince you to download the free app, it also offers a parking finder function, operating in 23 cities. If you've got an iPhone and a free parking space, download this app and thank us later.