Shoutbox

You can check your IP address each time you reconnect to see if it changes or not.

http://shoutbox.menthix.net/ip.php

What kind of Internet connection do you have? It might not be a good idea to host a site on your PC if it has a slow upstream, or if the computer can't be up 24/7...

Edit: BTW, I've got ADSL with a pretty bad upstream (96 KBPS = 12 kbytes/sec), and a dynamic IP address.