Welp, turns out I wrote an entire post about the Control-scroll zoom-in-and-out feature all the way back in 2006, when it was a new feature in Mac OS X 10.4 Tiger. Somehow, between 2006 and last year, I completely forgot about it. I don’t think it helps that the settings moved from the Mouse panel to the Zoom sub-section inside Accessibility. But I’ve used it so much in the last year, since rediscovering it, that I can’t believe I ever forgot it. Anyway, after I posted about it earlier today, a few people told me they could swear they learned about it here, long ago. They were right!