Check out this cool Roland synth emulation, the PG-8X

Originally as a 61-key polyphonic, analogue synthesiser in 1984, the JX-8P was marketed by Roland as the best of both worlds. It opened up the possibilities to classic analogue synth sounds and also to produce certain types of sounds associated with FM synthesis, such as metallic percussion due to several new modulation parameters and redesigned hardware. Developer Martin Lüders took it upon himself to do a free software emulation called the PG-8X v2.0.

Up to 12 voice polyphony.
Two DCO’s with Saw, Square, Pulse, Noise.
Hard Sync and Ring Modulation.
Two exponential envelope generators.
24 dB resonant LP filter.
HP filter (3 stages).
Stereo Chorus.
Import and Export of JX-8P Sysex data.
PG-8X 2.0 is available now as a free download for OS X & Windows.

Download here