PC Fan hack lets you scra... scra... scratch analog audio, ah-yeah (video)

Digital DJ controllers let would-be grandmasters get up to all sorts of fancy new tricks, but if you're one of those old dogs who can't be taught, then this PC-fan-come-DJ-turntable might tickle your fancy. Connected to an old-school personal cassette via an Arduino, with a little voltage level smoothing in the mix, moving the fan "scratches" the audio, by controlling the speed of the tape player. The initial plan was to have the fan spinning with the music, like a real turntable, but as you'll know if you've ever caught your finger in one of these things, it's probably best it didn't work out. Despite its home-made charms, one final flourish is VU style LEDs for some mixer-style visual feedback. Alas, there's no built in cross-fader, so don't start work on that DMC routine just yet.