Put windows server on it. It can handle multiple connections.

... so can Windows XP. Not that it'd do the OP any good; Windows Server's Terminal Server is expressly not what was needed, but rather a way to share the same screen across multiple users. Windows XP Remote Desktop is the closest you'd find, but that doesn't provide the service for multiple users.

Just OK
 

Here's an update: Using TightVNC Server and View works great at letting multiple people connect to one computer, all at the same time.

However, my colleagues (on a LAN) are complaining that it doesn't refresh enough. They will use a program (like Excel even) and scroll around or make changes, and not see it on the screen. Sometimes they'll open up a program and just see the outline of the window, but none of the content.

As a result, they end up just logging in with GoToMyPC or LogMeIn, which both work great but only one person can use at a time.

Anyone have a solution to this? Is there a better viewer? Or a different flavor of VNC that will allow multiple simultaneous connections?

This likely occurs because the VNC server doesn't notice all the changes to the server's desktop. You might try changing the "capture method" in the VNC server settings to poll for changes rather than using hooks, if such an option is available. It is available in RealVNC; don't know about TightVNC but it's worth a look.

Windows Remote Desktop
 

Windows Remote Desktop comes standard with XP Pro and can be slightly modified to allow for multiple users to login simultaneously. More information and walkthrough:

http://sig9.com/articles/concurrent-remote-desktop

Possible to view/control remote computer as well as share files and sound. Excellent solution without additional software. I find it much quicker than VNC.

@ ttjoseph: hmm... no "capture settings" anywhere I can find on TightVNC. Maybe I'll find a different viewer.

@ driftings: WinXP simultaneous users on Remote Desktop is interesting; unfortunately I checked out the link and each connection must be logged in under a different Windows account - we are trying to be logged in and seeing the same thing on the screen.

For remote application use, UltraVNC is much better than TightVNC. It does a much better job of seeing screen updates, since it actually uses a video driver to watch the screen.

Thanks for that. I am testing out UltraVNC now. Do I have to enable some setting or plugin or something to use the video driver you talk about? Is it the "optional Mirror Driver"?

Yes, that's it.