Ever noticed that stamped into the bottom of your glass carboy? Today I determined that you can indeed bump them. I had mine upside down balancing on the neck resting on a towel to drain dry. As I was bent over the bath tub rinsing out my blow-off hose it came crashing down, took a chunk out of the side of the bath tub, bashed the hell out of my elbow, and then I caught it before it hit the floor. No damage at all to the carboy as far as I can see! (I was expecting my elbow to start swelling but it seems fine too!)
Here's to fine carboys made in Mexico!
...and I plan on making a proper carboy drainer.