What do you use those extra buttons on the side of your mouse for?

pcgamer.com:

We have a surfeit of mouse buttons these days, and I found myself wondering: «I know how I deal with this cavalcade of stupid buttons, but how about everyone else?» Call me old fashioned, but I'm a three, maybe four mouse button guy tops. Give me left, click, right click, a scroll wheel, and maybe a cheeky thumb button for when I'm feeling spicy. My current mouse has nine buttons, including two set for DPI shifting right next to left click. I kept accidentally going from 1600 to 1200 to 800 while furiously clicking on heads or ordering around my party, so I defied the brain trust at Logitech and disabled them completely. I'll use a thumb button for melee or a special ability on occasion, with the other one reserved for push-to-talk on the tail end of curry night when I don't want to go burping on the Discord call. Meanwhile, I have a dear friend who's so hopelessly hooked on those weird mice with the full number pads on the side, he wouldn't even consider anything else when shopping around for a new one recently. For this Weekend Question I turned to the PCG staff and forums to ask:

What do you use those extra buttons on the side of your mouse for? Here are our answers, as well as some from our forum(opens in new tab).

Christopher Livingston, Features Producer: Whatever a game maps to the Left Alt key, I move to my mouse thumb button. I just find Left Alt to be too awkward to reach, a deadzone for my fingertips. Maybe in a farming game or something I'd leave it there, but an action game where it's got an important function (block/defend in Dead Island 2 is the only recent example I can really think of) I find it way easier on a mouse thumb button.

Tyler Wilde, Executive Editor: Thumb button is melee. In games which don't