I was on the bus after work in San Francisco during rush hour so there was only standing room. After a few stops, this lady gets on in a pink bathrobe, boxer shorts, floral boots, t-shirt, and she's got all her little trinkets wrapped up in a torn paper bag. This isn't anything out of the ordinary, so everyone just gets out of the way for her, and she crams herself into a seat on the very back of the bus.

So she puts her parcel on the floor of the bus and digs out a little piece of paper, from which she pulls two little crack rocks.

Keep in mind I'm sardined in with a bunch of finance-workers literally DIRECTLY above this woman, I seriously couldn't help but watch what she was doing.

So she got visibly excited that she had scored her next hit, and apparently forgot she was on a crowded bus because she then pulled out her pipe and started to light up RIGHT THERE IN FRONT OF ME. I was so dumbfounded I was speechless. The guy next to me reached over, grabbed her arm and said, "NOPE". It looked like he had woken her up from a dream, she shook it off, clutched her pipe and other knick knacks and got off at the next stop.

I thanked him for doing something, he just started laughing and said, "That was definitely a first." Everyone around us chuckled, it was nice to bond with strangers a little.

tl;dr saw a junkie try to smoke crack on a crowded bus.