You could probably make some money on a "proof validation service" where you charge all of the crackpots who think they've solved P!=NP to validate their proof.
Or, if you just happen to find an error, send that back. But the service is free if you don't!
From talking to the mathy-side CS faculty in my department (UofC), the crackpots all think they've solved it. Genuinely, honestly, and completely.
These faculty complain about getting e-mail spam and sometimes even visits and phone calls out of the blue from people who claim to have solved it and want their proofs checked.
Or, if you just happen to find an error, send that back. But the service is free if you don't!