Well I haven’t really tried this, but its worth giving a try.
1> Should have a PC / Laptop / Desktop with internet connection
2> An account in twitter (you can get one from here : http://twitter.com/),
3> A cell phone / mobile phone that supports internet via GPRS .
Here’s how you can possiby try and succeed to shutdown, restart or logoff your windows system from a cell phone / mobile phone:
1> Set up your cell phone to send and receive messages from twitter. Follow these steps.
2> Install TweetMyPC and learn how to run TweetMyPC.
Use both the features to shut down your PC / Laptop from your cell phone !