As requested by a dozen or more people, here's the Rollin' & Scratchin' synth tutorial. Ideally you'd have a 1984 Juno-106, as it has fully implemented midi control, but I'm using the 1982 Juno-6 as that's what I have. The workaround is that I had to use the arpeggiator with external triggers for the opening bit of the video. The other part of the sound is the Boss HM-2 "Heavy Metal" pedal. I'm using an original Japanese unit, but I imagine the later Taiwanese version will be almost identical. You could also try the MT-2 "Metal Zone" pedal too.