CCleaner a utility for cleaning the debris in the operating system. In the course of their work CCleaner (Crap Cleaner) is looking for and removes unused files. These include: cookies, history, visiting sites in IE, temporary Internet files, search strings, files, Recycle Bin, etc.
CCleaner cleans the following components:

    Internet Explorer
    Cart
    The Clipboard
    Temporary Windows files
    Windows Logs
    The list of recent documents (in the Start menu)
    The history of executed commands (Start)
    The history of the assistant search in Windows XP
    Obsolete Data Prefetch in Windows XP
    Memory dumps after crashes Windows
    Chkdsk file fragments

Advanced options allow you to clean:

    The cache priority menu
    Cash Tray posts
    The cache sizes and locations Windows
    The history of aid to the user
    IIS log files
    Additional Folders

Home Page: http://www.piriform.com/