Dawn, I don't know if this has ever happened to you, but sometimes I double-click a link...
...when all it needs is single click. The second click actually hits on a link underneath the link I meant to click on, and I end up at the other site.
This happens a lot when I have my "favorites" menu down and Yahoo! underneath. I double click a link on favorites and accidently click something on the Yahoo! page.
It's hard to spot because it happen so quick.
Michael