ONYX for MAC

Mac's may not get as many viruses as PCs but they still pick up a lot of junk just being on the internet.  A great cleaning program is ONYX-- it's free and safe and thorough.  Running it once a month will keep your Mac working at out of box speed.

For your PC needs-- and I still have one that acts as a backup station-- CCLEANER is pretty much the same thing just for non-Macs.

Both are free and programs I've been using for years.