Professor Television's Photo Theremin (just $79)

Doktor Future writes: "I recently purchased this Professor Television [I'm guessing that's him on the left] optical theremin. It took him about a year to ship it, but the email exchange was very civil and increasingly amusing over time. To make up for the delay, he also sent me a CD of his band , which is funky Christian absurdist electronica that you just have to hear to believe. This song is clearly anti-Darwin. Awesome.
"Anyway, The cool thing about optical theremins is that you get amazing effects illuminating it with the LED from an optical mouse (you hear the strobing effect as FM modulation). LED flash lights or flexi-neck led pen lights also work well, since the lens defects (i.e. flare spots) allow for some cool modulation opportunities. You can also cover the sensor with your thumb to block off almost all light, and slowly allow some photons (or heat from your thumb) to create LFO effects as the oscillator capacitor discharges. Awesome."