Yesterday I rode in with a frozen rear dérailleur and about a 1/2 mile from work the upper pulley wheel broke and I limped the bike to work. Left it overnight, took the bus home, and thought I had an old rear dérailleur to scavenge from at home but nope. And today took the bus in and on my lunch break walked at race pace to an LBS and bought a pair of new pulleys. Threw a new one on at the end of the day and rode home with the studded tires snapple, crack, popping until I'd roll over the black ice and they would go ominously quiet and I would hold my breath that the studs actually work (they do) and roll all the way home.