SlickHDR

An esoteric thing that requires a good ear and, from my experience, manual separation of channels (L/R or M/S done with splitting). So for me, it works best on mixes that "ran their course" but still need some polish, and you want to try a quick thing because you run out of time. For example, in M/S configuration and used carefully, it can give you very quick and very powerful stereo results on master; especially when you have no other "compositional' ways to pull that stereo up. However, it's sometimes hit or miss, and also you have to read the manual to have the slightest idea of what's happening at all, trust me. (In short, it's three compressors that work together and talk to each other, but not really.) Other than that, at this point I'm ready to say that it's tried and tested in the real world for multiple years, that it works and sometimes works as an irreplaceable thing, IMO - and I'm usually the first to hate on both compressors and black boxes.