Osc320 is a free Windows VST instrument.
Features :3 independant oscillators, with various shapes (sin, square, saw, ramp, sin+harm1, sin+harm 1&2, sin+harm 1&3, sin/square, sin/saw, saw/square, abs sin, white noise, noise 2, noise 3). Envelope control.
2 LFOs, controling almost everything, with speed based on tempo. 4 events controlers : activated with notes push and release, they change a value like a LFO.
16 notes polyphony.
LP filter with envelope control.
Freeware by Askywhale