Not so much a question, but rather a personal project which I believe the audio community could certainly appreciate! ...well, actually it's a project only the audio community could appreciate... :D
Phonopath is free-to-play, and the gameplay is as follows: Download a sound clip, manipulate it to find your password, and advance to the next stage. Puzzle concepts span basic processing, spectrograms, cryptography, music, etc...
It was released last month, and received a ton of solid feedback from sound geeks all over. Check it out if you got some time - it's pretty fresh stuff. :)