When I bought my bike the guy at the shop where I bought it from told me that there are more expensive sports out there, but I have come to realize that he was full of ****. (I know I know there probly are more expensive sports out there it just doesn't seem like it when you are a broke high school kid).
The worst thing that has happened to me is that one time I'm not quite sure how, but a link in the chain caught the edge of the front derailler as I was accelerating through an intersection. Needless to say it riped it clear off. The first thing the guy at the bike store said when he saw it was "ohh f***", but because the bike was only three days old they replaced it for free.
-Matt-