The Gator spyware
application not only stores your passwords and personal details (alledgedly on your own computer), it also builds a comprehensive profile
of your web
It records every site you visit, how you got there and how long you stayed there.
It also comes bundled with a nefarious piece of software called Offer Companion. This is a piece of ad-delivery software. If a person using gator visits a site with a banner ad for say, an online book store, this software is able to place a pop-up window with the same dimensions of the banner directly over the legitimate (paid for) banner ad, thus depriving the webmaster and the original advertiser of potential revenue. This is done seamlessly so most of the time the surfer isn't aware of what is happening.