I'm an old person, and old programmer and and old computer user. When I started using computer 25 years ago you were better off without a mouse because it simply didn't work so I became a keyboard user. Today I'm still a keyboard user, I know almost every shortcut there is in windows and IE and use them a lot.
One that I always use is the Alt-S shortcut in IE. In a web form when you have a button of type "Submit" you can do alt-s instead of clicking the button. This doesn't work in Firefox and it pisses me off every time.........I hate those program who are said to work exactly as Microsoft's product but don't.