Re: what did you do to your motorized bicycle today?
After discovering they exist, and they're a shelf item at my local bike shop, I bought a couple of 'chain adjusters'. In case I got the name wrong, they're the little doodads that stop your rear axle from creeping forward and putting the wheel out of whack.
After four years of swearing at my last bike's chains and often realigning the wheel, this purchase of two $2.50 parts has made me rather happy. The new build will be so much more of a joy.