A new bug has been discovered in Internet Explorer that can resulting in crashing. Luckily, this flaw isn't anywhere near as bad as former ones that could result in system compromise. Regardless, an updated machine running Service Pack 2 is vulnerable, and Microsoft is aware of the problem. A patch will be made available through the standard update cycle assuming they decide it is an issue that needs addressing. In the meantime - all you have to fear is a crashed browser.