Hi, I have been using Ccleaner for over a year now, I think its very good. Helped me resolve problems that I couldn't have fixed by myself.
I think, Ccleaner should have the ability to clean the Event Viewer reports for Windows. It has thousands of undeleted reports. More of them are created without you knowing it. It records log in durations, services that have loaded, error and crash reports, diagnostics and so much more. Vista has hell lots of it and so does Windows XP. You can open Event Viewer by typing eventvwr.exe on Run and OK. Collapse the categories there in the navigation pane and you have thousands of reports that you didn't know existed. They somehow consume memory.
Maybe it should also have the ability to clear backup files besides restore points that it can already clear. Maybe a little bit deeper registry cleaning and some tweaks on unoptimized computer settings. Feedback on this one please.