I used Copilot the other day to debug a Windows machine 1,665 miles away. It worked great.
After purchasing a day pass ($9.95), you get an invitation code and a little executable. Send the code to the other party. They enter it on the site, and they get an executable. The two executables match, because when both sides run them, they connect (the first one gets a “waiting” message until the other person runs their program). There’s a little window that runs to tell you how much time you have left.
I wish I had more to say, but there was very little drama after that — it just worked. There’s a bit of lag — it’s more VNC than Terminal Server — but still quite functional.
You can try it free for two minutes just to make sure it works before you buy.