The team at Native Instruments have announced a free compressor plug-in called SUPERCHARGER, which is free until the end of the year - it will then cost ¢49 to purchase.
The compressor is a tube based compressor and uses a simple one knob design.
Native Instruments say it can be used on a variety of material including vocals and drums, giving anything from subtle to pumping and crushing.
At the heart of the plug-in is the compress knob, then the user can add punch and dirt. It allows for side-chaining as well as a wet/dry knob.
Supported interfaces: AU, VST, RTAS, AAX 32- and 64-bit