Free VST Software Synthesizers by Audio Nectar
I make software synthesizers and I give them away for free. I make them using Flostone dsp robotics software.
VSTI Synthesizers:
Blowtorch
Want to make your own synthesizer? Give FloStone a try.
http://www.dsprobotics.com/
Note: you can buy Flostone from their website or at
www.image-line.com - from the makers of FL Studio