If you've scanned your PC in the last while with Spybot Search and Destroy and Ad Aware and found there's nothing wrong with your computer, it's not because your squeaky clean, it's because your software versions are out of date.
Normally, both of these software apps notify the user that there out of date, but that no longer seems to be the case, or so it wasn't for me.
To download Spybot Search and Destroy, click
here.
To download Ad Aware SE Personal Edition, click
here.
It's a good idea to have both of these programs as not all spyware removers are created equally.
Also, here is the link for the best Coolwebsearch killer available:
CW Shredder
If you use Internet Explorer even part of the time, you owe it to yourself to download all of the above software.