Peavey Spectrum DPM Bass Sound Module: Cool electric, acoustic, and synth bass sounds from a simple-to-operate MIDI module (one rack space). Gets those great retro sounds, including some really fat synth basses.
This works very well with the Yamaha G50 MIDI converter I also have for sale (see "Accessories" listings).
$80 includes shipping to the continental USA. PayPal or Money Order.