I just put in 2700 USD, the current balance of my bank account, and I'll find some way to put in more by the end of the challenge.

Wow. I'm impressed. This kind of gesture brings back memories of parable that still prompts a surge of positive affect in me, that of the widow donating everything she had (Mark 12:40-44). It also flagrantly violates related hyperbolic exhortation "do not let the left hand know what the right hand is doing". Since that is message that I now dismiss as socially, psychologically and politically naive your public your public declaration seems beneficial. There are half a dozen factors of influence that you just invoked and some of them I can feel operating on myself even now.