Autodafe has released B8 Organ, which is a reproduction of the old organs of the '60s and '70s.
B8 Organ has 9 oscillators, switchable between sine and saw wave, with drawbars, vibrato, chorus and reverb. Sine waves result in tones typical of a church organ, or "hammond-type" sounds. Saw waves sound more like old combo organs, like Farfisas, Davoli, Crumar, for example.
B8 Organ is free and is available for Windows as a VST instrument plug-in.