Logitech G903 mouse. Using a responsive mouse made computing more pleasant.
This is a personal nitpick, I'm glad this mouse works well for you & that's all that matters, but I hate the light on the "G" mice. When I was using one I covered it in electrical tape because the light was really bright and hurt my eyes when my hand wasn't resting on it (eg I was typing).
You can change it/turn it off. There's even a free software app to manage logitech mice: