Yes, this has been discussed several times. As far as I know there's no one working on it, it's a really hard work and there are a lot of things with higher priority.
About the donations, it's also been discussed, and most of the developers agree that giving money to someone that makes a port of an opensource emulator is a bad idea, you'll be paying someone that does the easy* job of porting it and nothing to all the people that wrote the emulator from scratch.
And even worse, people might start to port things just for money and some might start working on thier own ports instead of working as a team or helping other projects.
* easy compared to writing the full emulator, I know is not easy to port something like a N64 emulator