I noticed this nice howto on Digg a couple of days ago, it learns you how to stream video from your webcam to the Internet.
Here's a snip:
The first thing you’ll need to do is configure the machine you’re going to connect the camera to. You’ll need to install the drivers and software for your webcam, install the streaming software, configure the machine to use a static IP address, and disable power management—you don’t want the machine going into a power-saving mode.
To disable power management, open the Control Panel and go to the Power Options panel. Then make sure the System Standby option is set to Never. Make sure your webcam is working properly—most cams include an app that shows you the output.