I see you got yer Minimoog - I remember your WTB ads in the emporium way back. I've run a bass through my Rogue to pretty good effect and have run guitar through an Alesis Ion with good results as well. I got some cool sounds, but it wasn't worth the setup hassle to explore further - I had to run through a mixer to get a line-level, play a note, turn 5 knobs, play another note, etc.
Ha ha, I eventually suckered someone into buying my Callahamthe one that I never opened ($3250). Then I found a Minimoog (pre-upgrade) that was used by a satanic band who had first bought it from a church. I think that's great mojo.
I might find a rocker pedal to modulate the synth.
I tried to give you a few leads at the time, but Satanic Gear Trader Digest was off my radar back then.
Old synths are great - I remember spending a good amount of time getting a patch on my Alesis Ion (an analog-modeling digital synth) that I thought sounded really amazing and fat. I then plugged in my Moog Rogue and it just destroyed it - the Ion sounded flat and lifeless in comparison. The Ion is long gone, but the Rogue is going nowhere - 2-D vs. 3-D. It reminds me of comments made here by people who have played fantastic examples of vintage guitars next to their modern counterparts and said that there is no comparison. The third quarter of the 20th century was just a great time for analog electronics, and will probably never be bettered in that department.