I’ve heard all the false tricks, “turn until you hear it click, listen to the back of it until you feel it fall into place, etc.” but I want to know: does anyone know if there really is a secret to finding the combination to a standard, 3-turn Master combination lock? the curiosity is killing me.
you know, come to think of it, this might be one for Cecil.
Sure is.
Step one: Buy a lock.
Step two: Memorize the combination.
Step three: Get the hell away from my stuff. If I wanted you to be able to get to it, I wouldn’t have locked it. 
There used to be a way to dramatically shorten the “brute force” method, but it only works with older models.
Since this borders on the grey area of legality, I’ll just say that a certain respected technical institute of higher learning, situated near another respected institute of higher learning documents the techniques involved.
You’re on your own from here, unless a mod steps in and says it’s okay to post more.
Two words: bolt cutters.
Here’s a discussion from GQ:
http://boards.straightdope.com/sdmb/showthread.php?threadid=78438
Most of the solutions seem to revolve around breaking the lock rather than picking it by figuring out the combination, though.