Apple Remote

No, I'm not referring to that little white plastic remote you get with you new Mac, I'm referring to the Apple application available in the App Store. The Remote is a free application that allows you to control you're computer's iTunes library over your Home/Office Wi-Fi. It works by you finding your library on your Wi-Fi network, and then going to that library and typing in the 4-digit password that appears on your iPhone. This will not work over the iPhone's 3G or Edge networks. 

The Remote is a simple yet awesome app. It can turn your laptop/desktop into a wireless media center. This means that you can start videos with the Remote, along with music. You browse your library like you normally would on you iPhone, and then once you select a song, play it as you normally would. But, the Remote will send a signal to your computer to play that song and you can listen to that song from your iPhone (it plays on the iPhone as well) or from your computer. 

This is a great app in that it's free, it does something cool and useful, and you can scare friends with abnormally loud music as they walk by. Overall, download it, try it, and see how you like it. It's free, so don't be afraid to delete it if you don't like it. 

8/10