I am a fan of CCleaner and have used many of it's different features. I did find one dangerous feature. Out of the box, it clears out your Antivirus log files. I recently had a virus on our corporate network and just started stepping through my usual cleanup procedure which starts with CC. My boss's Boss's BOSS requested that I do an incident report and document as much as I could. The log folder was empty. I now use CCleaner-portable with a pre-configured .ini exclusively to prevent it from clearing AV logs. Just a thought!