Wesner Moise, a former Microsoft employee, writes about how his computer contracted a Trojan Horse, as a result of using Internet Explorer. Frankly, I was not surprised until I read the last paragraph:
I can't believe that it was this easy to become infected; I also couldn't believe that Internet Explorer could be so flawed as to allow an a security breach like this. This discovery led to my decision to install Windows XP Service Pack 2, despite my disinclination to run beta software on my main development machine. The installation was flawless, by the way.
Enter my simple solution. Unlike Internet Explorer, updated versions of Firefox come out regularly (there are even nightly builds available), and will run on all recent versions of Windows. Add a rapidly growing list of features (including integrated popup blocking, tabbed browsing, importation of IE profile information, skinning the browser using themes, and the ability to add new features through extensions) and there is no reason to use Internet Explorer as your primary browser.