I recently tried to donate money to a friend's charity. The page is hosted on Kintera.org, which includes a form to collect credit card info, and a Java applet that shows who else has donated recently. It uses a scrolling library they probably pulled off some untrustworthy website (I doubt it's the worse possibility - Kintera willfully infecting those making donations).
Unfortunately that scrolling library has 3 viruses, all of which act as Trojans to infect the user's machine and place them at the whim of a command and control bot network:
That's pretty embarrassing. The scroll page actually shows one page before you fill out your credit card info, so in the absolute worst case scenario, you view the page, click Continue while the infection is occurring, a keylogger downloads and runs, you enter your credit card info, and off it goes to as many as 3 bot network owners/users. Not cool.