When I look back at some of the people that I've shot (with my Canon, not a cannon), I wonder about their backstories. Like this guy for example, walking swiftly past a Fedex truck on Market Street. (He actually sort of looks like a fed). He was in a major rush to get to wherever he was headed, a very grim impression on his face. Was he late for a meeting with a client? A mobster looking for Fat Tony? Or maybe he was a Fed. We'll never know for sure...
I'm not a real big fan of doing black and white when shooting digital, but I do like to tinker with it every now and then. B+W is also something I use when I overexpose something, like I did with the Fed guy on a very sunny day. I try to adjust the highlights and shadows and contrast on Lightroom instead of just going by the preset B+W button. Makes for more interesting photos afterwards.
Just don't turn into one of those people who click a button to make a B+W photo and call it art.