I just received a big delivery from Sparkfun, with lots of components to experiment with (I’ve got a Lilypad, an Arduino Fio to experiment with the wearable aspect of biosensors), a few new Arduino Uno, and the MP3 shield to experiment with sound and a few sonar sensors.
If you go back and read the original idea, we want to collect how people react to external inputs, and the first (and easier to implement) is sound.
The experiment we made so far is wiring up the MP3 shield, add a sonar, trigger different sounds based on how far (or close) a person is to a wall.
Working with the MP3 Shield is pretty hard: there are no easy to use API, but you have to code directly against the MP3 decoder chip, feeding it with buffered arrays of bits. At least Sparkfun released a tutorial and a lot of sample code, and all you have to do is copy, maybe include it into a reusable library, and use it into your code.
Here is a short video of the testing of small device we made: