iPod -> audio recorder
For several weeks, I have been pondering the following: speakers and microphones are pretty much the same, in that they’re both bits of piezoelectric material held next to magnets with wires coming out of both sides. The only difference is that current is imposed on one and the other imposes itself on the current instead. Consequently, it seems like you could take your headphones and use them as really crappy microphones to record sound wherever you go with an MP3 player, assuming you made the correct changes to the firmware. Well, it turns out that not only is this possible, but people have already done it. In true hacker form, the first step is to install Linux on your iPod. I don’t think I’m actually going to do this in the foreseeable future, but it’s nice to know that someone else has tried it and it works.