I use ShowMyPC.com frequently and it has the advantage of OS independence (Windows, Mac, Linux). Any OS can share with and be controlled by any other OS. It also has good performance even though it's running via SSH for security. For Mac and Linux there is a Java applet. For windows, there is no install, just the download. Use it.

Isn't this Slashdot article pointing to the answer? http://tech.slashdot.org/article.pl?sid=09/07/03/1248246 Check out: http://www-jpc.physics.ox.ac.uk/applications_cloud.html

I was going to add the same tips. One additional application type I highly recommend is anti-keylogger software. There are a couple of different apps out there that are free and I recommend using at least two of them. This will decrease your exposure but won't prevent root level key loggers or hardware based key loggers. Best of luck!