Uncover the Net Toolbar. Here is a nice tool that I recommend you take a look at and perhaps install. It is eliminates pop up ads, searches for sites using Uncover the Net, Google, Yahoo, MSN, or Ask Jeeves, and checks backlinks to a site using Google, Yahoo, or MSN. There is no spyware or adware attached to the tool either.
I have installed the toolbar and will give it a try for a few days. So far it looks good.