I put a new KMC chain on my fixie and got everything all tightened up, chain was set extremely tight, so I took it out for a spin and it was working great. Skidding was no prob, chain tension felt great. Well, I'm coming down the biggest hill in downtown Grand Rapids and skipping here and there to check my speed when all the sudden, *ping!* and there goes my chain... mind you this is maybe 1/4 of the way down, and there are 5 traffic lights before you get to the bottom, not to mention they are all red and there is cross traffic. I'm dragging a shoe, its not doing a whole lot. I'm starting to think about laying the bike down and letting my bag take the impact, but I'm going 25+ so the thought is a bit scary and definately last resort. Finally, just as I am approaching the first bigger intersection the light changes, cross traffic clears and I can make a really hard right turn. Thankfully I was able to stop pretty quickly since there was a slight uphill on this street, but my heart was still racing. Closer inspection revealed that the chain had stretched essentially an entire half link on one hill's worth of riding. Chainline was ok, but I guess the backpressure just popped that chain right off. Anyways, I said screw it and today called my boss and had him order me one of those chains thats made entirely of half links. Chain stretch kiss my ass!