It's a bit of a quick hack as it's a CLI app, so I just made a script that prompts for the binaural beat file (.sbg format) and plays it in a terminal window. The first app I've ported to Pandora, and the first PND I've ever made. It should work correctly, but let me know if you have any issues.
Update: I also added a shutdown when done option, and if you want to save even more power you can clock the Pandora to 200mhz, and if you have hotfix 4 close the lid to turn off the screen.
I haven't posted it on the file archive or app store yet, if anyone wants to do it please feel free to do so