Why not? Realistically, this technology is out there. Anyone who wants to can do what I'm doing - it's not anything radically unique. If you are storing passwords with a good algorithm (salted, minimum length/complexity requirements), this doesn't bother you at all. If you aren't... you should be! md5($pass) is NOT a good password storage system! Never has been, and is about as bad as plaintext right now.
Why should I donate?
To support further development. Top of the line GPUs (or even the low end versions of the latest generation) are not cheap. The sooner I have the money to buy them, the sooner GPU-specific optimizations fo the latest generation are likely to appear.
I have this top of the line GPU and 1.5kW power supply laying around doing nothing... could you use them?
Absolutely! I'll even pay shipping for nice hardware.
Why do you release cross-platform tools?
Because it's silly to release a tool for just one platform when the technology exists across all of them.
Why aren't there tools for BSDs? BSD is superior!
Because nVidia does not support BSDs with CUDA.
I don't like the ads!
If I make enough between selling software and donations to cover my costs, I'll drop the ads. Believe me, I don't like them any more than you do, but I do like being able to fund GPUs more than I dislike ads.
I have another question!
To the forum with you! I lurk there and try to answer questions promptly.