Mine's an easy lesson - don't ride really old tubulars. But I was prepared with my [lumpy] YJ spare.

Although I did determine that my super glue worked as intended. I had an old Vittoria Mondial that I knew was near the end, and had multiple slits and cuts in the tread. I used superglue in each of these cuts, and all those held up fine. The loud bang ripped the tire apart across the entire casing. Pretty amusing, actually.

And granted, it was a rear tire (I'm only a partial fool, wouldn't have ridden it on the front), but I had absolutely no loss of control during/post-explosion. Tubulars are really nice that way.