Microsoft
Microsoft used to make the best mice in the world, but for reasons that have never been entirely clear to me, the company decided to give up on this a few years ago. While the company has continued to make a number of interesting and unusual mice, for the last decade or so its focus has primarily been on mobile mice—the kind of thing you'd chuck in your laptop bag—rather than button-laden feature-rich desktop mice. When my Intellimouse Explorer 3 died after many years of use, I ended up switching to a Logitech Performance MX, because Microsoft no longer had anything comparable.
Announced today, the Surface Precision Mouse may be something of a return to form. It's a full-size desktop mouse. It's an ergonomic design that's only really suitable for the right-handed—a design that seems extremely familiar to users of the aforementioned Logitech. It has a wheel, of course, and the wheel has a button that toggles between notched mode, beloved of gamers, and free-wheeling mode, designed for scrolling and zooming. On the left-hand side, it has an array of three thumb buttons. It supports both wireless connections over Bluetooth and wired connections over USB. When using Bluetooth, the mouse can pair with three different devices simultaneously and has a little switch on the bottom for picking between them.