Would you open source it for a 400 BTC bounty ?
Well, out of respect for previous buyers who spent their hard-earned BTC on it, no, I should not...
I'd rather be inefficient than proprietary. The client looks nice though! Is it using OpenCL?
To be honest, I think if you get youtipit or a web page describing your effort with the repository and a donate address, you'd make plenty too. And + on happiness and goodness in the world.:)