If you don't like X10 ads, you guys need to check this link out. It sets a cookie that the X10 ads check for. If it exists, the popups immediately close themselves. The default is for 30 days, but you can change the day variable to anything. I change it to 365 myself. I figure that's enough.

http://www.x10.com/home/optout.cgi?DAY=30&PAGE=http://www.x10.com/x10ads1.htm