Noise Vibrations!
Digging through these old Easyriders is fun - you learn so much! I found the sextoy below in one of their 'recommended purchases', right below the beer-can sling you hang around your neck and a folding shotgun. An audio-controlled vibrator? That's awfully high-tech for the seventies; I didn't even know similar products still exist, updated for the iPod generation. One difference is (and the picture doesn't show it) that the 1970s version had a separate amp box, which doesn't sound too comfortable during practical use. I imagine that, a handy person could take out the low-powered amp it came with and put in a nice Mcintosh tube amp for rumblier lows. That's the thing with off-the-shelf audio equipment: it's always a good idea to replace the important parts with something a little more high-end.
Via.