It is freeware now. And you can do cool synthtunes with it .
Old for sure. But it has build in synth so no VSTi support.
So it is cool for that. It is like virtual soundchip ).

This is a very old one, I didn't know it went freeware now it used to be paid software.
You can make some cool acid basslines with it.

It is free and can do chiptunes too...
http://www.audio-simulation.com/?page=product3

From web>
"Up to three oscillators can be used for each voice, where every oscillator is generating sine, triangle, sawtooth, pulse (OSC2&3 square) or noise waveforms. Linear frequency modulation, ring modulation and hard synchronization are available between OSC1&2. You may replace the traditional waveforms with 16 bit mono samples, and use them as the source of ring and frequency modulation. A multimode filtering architecture is responsible for eliminating/exciting specified frequencies of the generated signal by supporting 2 pole lowpass, bandpass, highpass, 4 pole lowpass and formant filter modes. Three ADSR envelope generators (each one individual for the amplifier, filter and a user defined EG for general purpose), one LFO, vibrato and portamento are the modulation sections."

When somebody will tracking with it email me, we can change patches...