Once I was doing a job for a small company, and the guy who hired me asked me to name a fair price, and I said $175. Weeks later when the job was done the guy accidentally sent me an email meant for his business partner where he was like "I'm feelin crazy - what do you say we pay him $500 instead? Should we or shouldn't we?"
Ten minutes later I got another email from him, saying "Uhh, I guess I'd look like a dick if we didn't go ahead and pay you $500, so, congrats." That was a good day for me.