OK, so I'm a complete moron. It's 12:50am on Saturday, which means that I leave for a group bike ride in 7.5 hours. I found my bicycle computer, and my bikes on the bus pass, which means that I can actually get to my ride. I also managed to swap the front tire on my bike twice tonight. I swapped first for a "spare" kevlar with a wire bead that I had around (it was giving me flats on the back, but I've determined that I need a steel-belted tire on the back to avoid that). As it turns out, that tire has "high" sidewalls, and was rubbing against the rivets that help hold my fender in place. I can't move the fender at all, so I guess I just need to stick with low-sidewall tires. Anyway, I'm using the tire from my track bike in the mean time. I think I'll put the original back on there. It looks a bit worn, but I've never had a flat on it. In fact, tonight was the first time that I've taken that tire off in the past 3 years. BTW, by worn I mean that it's slightly flat where it contacts the road, and it's got some tiny "cracks" in the rubber. From the inside, it looks perfectly fine, and there's still 3/32 of rubber left there, so I think it's probably safe.