Disk Diag

Clean your hard drive with just a few clicks

Hasn't been updated in almost two years (this means, neither Yosemite's nor Sierra's special needs are being considered), has about five nag- and upsell-screens popping up, and doesn't really do anything any of the free or more powerful solutions offer.
@legerdemain Clean my Mac is the go-to solution for us. Not cheap, but it does the job well and keeps older Macs useful.
Why hunt an app or product if it's not being updated?
@mirmayne Because it hasn't been hunted before, I find it useful, and I thought other people might too.
I've been using Disk Diag for a while as a quick and easy way to clear out my trash, temp files, and caches in one fell swoop. Takes literally seconds to run and has a pleasing interface!
@riaface As Mikka and Daveyon say: it's a bit of a mystery as to why you hunted this. This hasn't been updated for ages and it's not compatible with the latest and greatest OS X's. Sure, it's fast and pleasing, but I rather prefer reliable and frequently updated.