AcmeBarGig recently released Mr. Tater Head, the last release in the "Preampus Classic Hybrid" line of free amp VST effect plug-ins for Windows.
Mr. Tater Head has three different gain controls - Bass Gain, Mid Gain and Treble Gain - as well as the standard Bass, Mid and Treble controls on its tone stack. These extra gain controls mean you can really get in to shaping the sound of the saturation. It takes some tweaking but AcmeBarGig says that you can get some really unique tones through altering the overall gain control and the three extra gain knobs.
The Preampus Line amps are Head ONLY so you will need to use some external cabinet modeling.
