Trains are usually crowded during peak hours. Everybody will push each other to try and get onto the train. How can I protect my personal space? The idea was then conceived. "What if I wear a vest that is full of spikes?"
That's an unusual train of thought! (pun, unfortunately, intended). More details at CNet.
The Parisian public transit authority has issued an illustrated etiquette handbook [PDF] for riders of the metro system. Nice idea, but I'm guessing that it'll only be seen by those who don't need to read it. [Globe and Mail]