Ask YC: P = NP ?
What's your idea?
Has it been solved in secret? Are we not smart enough to solve the problem? Is there little incentive to prove that P!=NP? Do foolhardy attempts produce "good enough" improvements to existing practices?
Except that the answer is quite likely P != NP. Rather than characterizing the rewards in financial terms, IMHO the more important thing to be gained is knowledge: the answer to a fundamental question in complexity theory (perhaps the fundamental open question).