I love this. eBay item 180141928515 is a MODboard onboard analog delay circuit - a little board, powered by a 9v battery, which can fit into the cavity on your guitar. You can then add a couple of knobs (or use those stacked pots) and have live tweak-a-tron delay right in your guitar. It's also cheap - the full kit, including the board, push-pull pot, battery lead etc - is just $51.95. If I was a soldering minded chap, I'd put one of these into a project guitar and mount a little analog joystick to control delay time and feedback. Even if you're not a guitarist, this could be good for all manner of circuit bending fun. I wonder if I could fit one in my Synth II?