Ok, so it has been a couple years since this shot and since I have finished my 365 and I still occasionally get emails asking about, I am going to spill it here. I know Alex Rubio will be very happy to finally know this. You can read the original post here:
Michael's 365 - Day 177
There are some really good guesses on that thread, and if you haven't seen it, its a good exercise. Some of the suggestions offered would have worked.
When you are ready for the trick, the password is "day177".