average keypresses over the length of a song to find the BPM
This script plays a song file (in Ogg Vorbis or MP3 format) and lets you
tap along on the spacebar, calculating the BPM (beats per minute) in the
song as you go. It also gives you an offset in milliseconds of when
you started tapping, compared to when the song started. You can then
use these two values to create a step file for that song.
This is only as accurate as your sense of rhythm. :)