Mercuriall Greed Smasher

Mesa/Boogie® Grid Slammer modeling.

Guitar processing plugin. It is a highly detailed, circuit-based model of the Grid Slammer overdrive pedal by Mesa/Boogie. Being a virtual overdrive pedal, the plugin is aimed mainly at guitar players and music producers who use distorted guitars in their music, although effects like this one can work equally well for processing virtual instruments and even hardware synthesizers.

The user interface is a replica of the Grid Slammer guitar pedal, featuring a bypass switch and level, tone, and gain knobs. The top panel adds a mono/stereo input switch and a low/high processing quality switch which toggles between 2X and 4X oversampling. The desired input gain value can be typed in by clicking the black bar at the top of the GUI.

https://mercuriall.com/cms/details_freestuff

Harmonics

HoRNet Harmonics is a wave shaper based on the Chebyshev polynomials. Its non-linear processing lets you adjust the level of harmonics added to the signal, warming it up in different ways.
The plugin provides 10 harmonics generators of which you can set the amplitude and phase, increasing or decreasing the impact of the harmonic on the input signal. The resulting sine wave equivalent shape is displayed on the right side of the GUI.

HoRNet Harmonics provides great flexibility and lets you create interesting distortion, try for instance to remove the fundamental frequency (set the first slider to zero) and create a “broken record” sound, or use one of the provided preset to explore the different possibilities offered by the plugin.

https://www.hornetplugins.com/plugins/hornet-harmonics/

BlackBooster

BlackBooster is a free audio plugin for Microsoft Windows, booster stomp emulation, based on real scheme.

- 64-bit internal processing
- input level adjustment
- mono/stereo processing

www.nsp-vst.ru

Mercuriall TubesCreamer

Drive/Distortion effect
The modeling is based on a real circuit of the Ibanez TS-808.
Mod switch: "808" for a default sound of the Ibanez TS-808 and "Mod" for getting a cleaner sound with slightly more bass when "Drive" is at the minimum.
Low CPU usage.
Stereo and Mono modes.
Low (no oversampling) and High (4x oversampling) Quality switch.

http://mercuriall.com/cms/details_freestuff

HY-MBDrive

HY-MBDrive, a free multiband drive VST effect plug-in for 32- and 64-bit Windows.

You can set drive, pan, stereo width, volume per band. Also you can choose a drive algorithm.

http://hyakken.moo.jp/WordPress/product/hy-mbdrive/

TSE Audio

http://www.tseaudio.com/software.html