Voxengo has released Boogex, which is a FREE guitar amplifier VST plug-in with a variety of sound shaping features.

Features:

• Emphasis and Cut Filters. These are used to shape the sound of an amplifier.
• Pre-filter. Used to filter the incoming guitar signal. This is usually useful if the pickups on the guitar are too boomy or too crisp.
• Amplifier. This part is usually represented by a single Drive knob on actual guitar combos. The concept has been refined in Boogex and it is possible to get very different overdrive tones using four knobs. The Tone knob adjusts the character of distortion (or selects 'channel' like in some guitar combos - from clean to overdriven). With low tone value you will get a mild distortion, while with higher tone values distortion will be heavier. Dynamics adjusts the dynamic response of the amplifier - its effect is most evident with low Phase parameter values. The Phase parameter adjusts the overdrive performance - it is possible to fine-tune harmonical structure of the overdrive - for example if you hear too much discord tuning the Phase parameter may help. In some cases Phase also works as a mic displacement control - you can get different degrees of tone with it.
• Speaker cabinet impulse response selects which speaker cabinet model (and mic) to use. Loads WAV or AIFF audio files.
• Processing latency is very modest - 96 samples (2.1 ms at 44.1kHz).
• Several example factory presets are included.

Boogex is available as a VST effect plug-in for Windows and it is free.