Well, that is a bit of a tricky question. I only have IE8 installed, however, I do use IETester to debug xHTML/CSS as I develop sites. Although, I've never had this happen before and use Firefox primarily.
I ran CCleaner for about 12 hours on secure delete (35 passes) and when it completed I got the following:
I bet Google would love to barrow some of my spare hard drive space... lol Anyway, I found it funny that the IE Temp files that got removed were twice as large as the total amount removed.. (Neither of which are anywhere near accurate.)