What is it?
As a big N64 fan, a few years ago I wanted some way to try out my homebrew on a real console, play translations, and just to mess around in general -- but from looking at all the other solutions on the market there appeared to be tons of room for improvement and I started to make my own.
After a lot of work and several years of iteration since then, what you see is the result.
It's an extremely high quality product used by hobbyist and professional developers alike.