HRNG - Human Random Number Generator You know it: keyboard or mouse input is just too mainstream to create Random Numbers through human behavior.

Create the most unique (Pseudo)Random Number Generator that create its numbers through human behavior.

Web-API's are not restricted! Anyone should use the code provided, so any special hardware is restricted. (I think we can assume that everyone has a smartphone)
The number should be a 256 bit number.

Example: use the Google Map's API to get current traffic to create the Random Number.

This is a popularity-contest, so most votes wins!
Mathematica on Mac OS X

Mod[Tr /@ IntegerDigits[
  Floor[2^15 AudioData@SystemDialogInput@"RecordSound"]
, 2], 2]


Opens up a dialog box that lets you record a sound snippet through the computer's microphone, then converts the resulting digital audio data to a list of bits (roughly 50,000 bits per second of audio). Generate random numbers through white noise, singing your favorite tune, exclaiming "Serenity now!", or just yelling at the top of your lungs!