Disk Cleaner is a free tool to quickly and easily free disk space that is used by temporary files like those in the system temporary folder, the Internet Explorer Cache and Cookies folder, and the Recycle Bin.

From the author's site, "With Disk Cleaner you can easily clean up disk space that is now used by temporary files like those in the system temporary folder, the Internet Explorer Cache and Cookies folder, and the Recycle Bin. Disk Cleaner was inspired by one of the system tools that can be found in Windows 98. As I was running Windows 95 myself those days, and upgrading my machine to 98 was not an option, I decided to write such a tool myself. However, Windows 98+ users may find that Disk Cleaner is smaller and faster, and one of its virtues is the ability to run quietly, i.e. on startup. This means that you can clear the cache every time you boot Windows".