VNC
My mom was having some computer problems, and we tried to work on them over the phone, but it wasn't so great, because I'd have to tell her things to try, and she'd have to read me the results, and you know the bandwidth in that situation is really low -- well below 300 bps between the remote user and the computer if the computer operator isn't familiar with what you're asking him or her to do.
So I got my mom to download and install a VNC server for Windows, and I grabbed a VNC client for MacOS (I'm using this iBook at the moment, mainly just to ssh using the wireless LAN here), and in a few minutes I could see and interactively control her entire Windows XP desktop. VNC is great. Next time you're trying to help someone with a computer problem from far away, get VNC and get it set up first.
(It will help if both people have network connections faster than 56 Kbps, though...)
One of the cool things about VNC is that it's so cross-platform. Unix users can control a remote Windows desktop, Windows users can control a remote Unix desktop, Mac users can control a remote Windows desktop, etc. (There is a vncviewer in LNX-BBC, although currently no working X11 out of the new build tree.)
Intrepid readers of mailing lists I'm on may recall that there is even a PalmOS VNC client, and I once used that client together with a Ricochet modem to type characters into an xterm running on my Unix desktop system while standing in the middle of the room squinting at my Palm Pilot's screen. (Easier than that is to use one of the ssh implementations for PalmOS and create a text session -- but the graphical session did work! I call that inappropriate technology.)
