Cleanmem works in a matter of about 5 sec. It uses a windows api call that is in Windows 2000,xp,2003,Vista & 2008 that tells windows to cleanup the workspace of a processes thus freeing up any memory the process no longer needs. Other memory cleaners end up forcing the memory into the page file slowing down your system. This tool does not. The API call frees up unused memory from programs, when a program needs the memory again it can simply take it back instead of forcing the memory out of ram and into the page file.A good example is this, say you have QuickBooks installed and setup for multi user mode.....(free).....