Does not do much but does it very well

This app cleans stuff that you wouldn’t know how to get rid off otherwise like downloaded mail, browser cache, etc. I use it regularly and will typically regain 3 to 5 gigs of disk space. Use it with Onyx and a duplicate files finder (there are many good ones) and you’ll be a happy camper.

HeavyDuplicator about Disk Diag, v1.4