Has anyone considered the possibility of building their own Taurus with your Slim Phatty? All you’d really need is a pedal controller, which you could make out of an old Taurus pedal set, or a set from an organ or something.
That has been discussed at a swedish bass forum.
Fatar makes midi bass pedals that propably would be great together with the SP or the Voyager RME.
http://www.thomann.de/gb/fatar_misc_accessories_for_keyboards.html
I think Roland has some too …