I love CCleaner, been using it for years. I always hated the fact that I couldn't clean the rest of my HDD with it though. Old Word documents, Excel documents, anything I deleted in my recycle bin by mistake before running CCleaner made me sad
And today I update my version of the program and find a Wipe Free Space option?
To deal with my aforementioned sadness, I began running Darik's Boot and Nuke once every year to delete the entire hard drive. I was also using this program when selling old hard drives (35 pass gutmann, usually two rounds of it...took close to a week).