If you are at PDC, you can go to http://pdcvibe and download the PDC 2003 community app. Sure, there are some quirks with it (it overlays the task bar at the bottom of the screen, and the navigability is less than desirable), but it is still a very cool application.
Once you download the app, you can select sessions and add them to your sessions.
The reason this is cool is that you can set up your profile for the community and see who else is attending a session.
Once you find someone you want to locate, you can click on their icon and see whatever information they chose to share, including web address , blog rss url, and MSN IM ID.