Sometimes during development with C#, you have to clean up temp directories. Ones like
"%homedrive%%homepath%\local settings\Temp" or maybe
C:\Users\YourUserName\AppData\Local\Temp
In pruning things one day I found the Windows/Prefetch directory and figuring it had well over 50MB of files, I figured that'd be a great candidate for pruning. hhhhmmmmmmmm........
Bad idea! Why NOT?! Check out Google's search for Prefetch findings.
http://www.google.com/search?hl=en&q=windows+prefetch
The first one that comes up (at least tonight) is from velocity reviews titled Computer Support - Clearing windows pretetch files. The crux is, Windows is using that location to store temp files to help speed up loading applications in the future. By deleting those files, you might gain that 20+MB of HD space, but at the cost of the next time you load up one of those applications, Windows will have to do a lot more work. AND on top of that, Windows is JUST going to put stuff BACK into that prefetch directory anyways! AND besides, if you're 20MB is going to "break the bank" you REALLY need to look at getting a new computer or at a minumum a new hard drive.
Hey, I'm just saying. But now it's time to grab another coffee and get coding!
Resources
Wikipedia: Prefetcher