Samurai Detective is a game that (for the most part) was created by the 15 or so participants of Bar Camp Portland 2012 during a 50-minute introduction. Bart Massey did a lot of the actual writing, with help from Audrey Eschright and Reid Beels.
Try the game here.
Samurai Detective is released under the Creative Commons Attribution 3.0 United States license: http://creativecommons.org/licenses/by/3.0/us/
Can you solve the mystery? HINT: Yes.