I used Collatz conjecture as a part of an anti-cracking scheme in one of my projects. There was an obfuscated .exe consistency check, but it was not run until f

I used Collatz conjecture as a part of an anti-cracking scheme in one of my projects. There was an obfuscated .exe consistency check, but it was not run until few other parts of the code (mostly rare event handlers) iterated a very long Collatz sequence down to 1. I figured if a cracker knew about hailstorm numbers, I was cool with him messing with my stuff ... and if he didn't, at least he would learn about it :)