Symmetric Microsoft Basic Optical Mouse, configured for right-handed use but on the other side of the keyboard. I left-click with my left middle finger, and scr

Symmetric Microsoft Basic Optical Mouse, configured for right-handed use but on the other side of the keyboard. I left-click with my left middle finger, and scroll and right-click with my left index finger. It's great having the mouse to the left of the keyboard - so much less distance to move my hand when I switch from the keyboard to the mouse! (I used to just use a mouse right-handed, but then RSI/OOS kicked in and I switched over. I wish I'd done it sooner!)