My “media center” PC is hooked to my television. I don’t want to dedicate a monitor to the system since the video output is going to primarily be sent to the television, but sometimes I need to view the screen as if I was working with a standard computer display. Remote Desktop worked well enough but it only works from other Windows machines and have an OS X based G4 Mac that I often work from.
I installed the UltraVNC server on the media center computer and the client on a couple of other computers. This version of VNC is very fast. When I start an iTunes bought episode of Battlestar Galactica the VNC server manages to push several frames across without slowing down the standard window display and mouse movement. The only little quirk is that Yahoo! Widgets aren’t visible when using UltraVNC.