If the filename is a lot of jibberish, and it mentions IE, then it is probably IE's cache. This could be the IE attack that Nimda launches.
No matter whether you see anything wrong with your computer or not, make sure you are clean! Sure you don't see anything, but someone could easily have slipped a trojan on your computer and is watching everything you do, grabbing all your passwords, etc. Go to http://www.antivirus.com and click on home user and click on the housecall service to get your computer scanned by a second source (for free too).
