I just discovered this although I suspect it's likely been around for a while. It's a virtual shortwave radio that allows users to tune in shortwave stations around the world with an online receiver. You can select whatever frequency you want to try using your keyboard, move up or down the dial in small or large increments, adjust squelch, use noise reduction and see how your reception is in a moving graph.

Perhaps the best part - it gets you out of North America, because the electronic SW radio is located at a university in The Netherlands. So you can hear what they would receive there. 

Even if you're not a big shortwave listener, it sure is fun to play with!

You can access it here.