If you can 'hack' me, I'll give you $300.*
Consider this a challenge. Hack me, and if you contact me with the exploit you discovered, how you found it, I will pay you. There is one condition, however: you don't share the exploit you discover with anyone else and you do not exploit it on me beyond testing. I acknowledge that what does and does not constitute 'testing' is ambiguous and extremely subjective, but it will have to do.
I will not define 'hacking,' nor will I say what does and does not count as a successful hack. What I will do, however, is give a general idea of what I mean: break into one of my online accounts or identities, discover information or data about me that is supposed to be private, gain partial or full access to a server under my control, or exploit any of my projects (see md-c.com). This list should give you a general idea of what I'm going for. If this were a legally binding offer I would be more precise, but it is not and so I won't. I will, however, keep my word.
I'm offering the money because I want the value of coming forward to me with the hack to be more valuable and worthwhile than using the exploit. It also gives you plausible deniability—you could explain why you were trying to hack me with the reward.*The amount is subject to change based on the severity of the 'hack.' Based on the severity of the exploit discovered, payout may be reduced to a minimum of $50, or raised to a maximum of $1000.