When I'm on a desktop I'm a keyboard guy. When I'm on a laptop with a USB mouse, i'm mouse man. Center clicking is the greatest thing since Alt+Tab and the Vertical Scroll Wheel, especially when you have a mouse like
this where you use the little red button and you can middle click with your thumb! But keyboard stuff if you have a comfy keyboard is 30 times faster.
If there ever was a useless feature I got on a mouse, it's definetly the side scroll, my mouse has it and I don't use it. Ever.