First of all, I don’t say products are good if they’re not. I’m a picky cantankerous bastard.
That being said, this is less a product review than just a “buy this, people,” statement – much like I endlessly say about Crashplan, which if you don’t have, well, WTF, get it.
Way back when pterodactyls roamed the skies and OS X 10.6 was released, Apple added transparent compression to HFS+ file system. However, there was no easy way to turn it on. Enter Clusters, a (very fairly priced) payware app which does so, adds exclusion lists, only turns it on file-by-file when your system is idle, etc.
Anyway, I’ve been running it for like two years, all my disks are over 90% full, and it just happily (yet unobtrusively – thanks for that touch, LateNite) informed me that I am wringing an extra 362GB out of those drives due to its efforts.
Mac users, just go buy it if you have the slightest problem with running out of disk space on your internal drives. (Obviously, don’t enable it on scratch disks for Final Cut, etc.)