Over the years I feel I've got very good at tracking down reasons for crashes in C and C++ programs, and I quite enjoy the experience of tracking down such bugs.
I've often fancied a way to monetise this, maybe even a "no fix, no fee" system (assuming you can give me a way of reasonably predictibly reproducing the crash, even if it needs a while / has a random element).
It would require the company giving out their source code to me, and giving me a way to build it, so I imagine in most situations it wouldn't be worth the effort, unless the bug was absolutely mission-critical.