TweetMyPC is a free program which lets you control your Windows computer using Twitter. That’s right, all you need to do is install the software on the target PC, set up a special Twitter account for the machine (disabling public access via the Protect My Tweets setting of course!) and log in on the PC.

From then on you will be able to shutdown or restart your computer, grab a file from your hard disk (via your email account) or even take a screenshot just by sending a tweet. You can even create your own custom commands (switch on my security cam, for instance). There’s also a Mac version too, called…ahem…TweetMyMac. Clever eh? .NET required for the PC version.