Terry West has released MHorse, a freeware compact mastering multi-effect unit in VST plugin format for Windows.
Another alternative for the CS12M series plugins. Smaller GUI, less options for faster results.
MHorse is available for free download via Terry West (2MB download size, 32-bit VST plugin format for Windows). The plugin features a 13-band graphic equalizer with variable bandwidth, HP and LP filters, tape saturation, DC remover, and several other tools. MHorse is basically a more compact version of several other mastering processors designed by Terry West. Browse around Terry’s website if you’re looking for more free mixing and mastering tools. I must admit that I don’t use his plugins, but I do like the idea of having multiple useful tools in one plugin!