I walk home most nights, and it's typically an uneventful walk. However, tonight I noticed a strange organic-chemical smell about halfway home; since I was nowhere near a chemistry lab, this was odd. A few hundred feet later I discovered the source: a couch by a dumpster was on fire. The couch wasn't bursting into flames, but smoke was clearly pouring out of it.
I don't have a cellphone, so couldn't call the fire department myself, but I had noticed two men closing up a shop just a short distance away. I walked over, introduced myself, and asked if either of them had a cellphone, explaining that there was a couch on fire. They looked at me like I was babbling nonsense; one of them mumbled something like "No phone," and the other just stared in the direction of the couch. After a few awkward moments of silence I asked again, repeating the word "fire," and they said "Um, no, sorry; try the store over there."
I'd seen one of them turn off the lights and lock the door; he could easily have opened the door and called the fire department. Instead, he just stood there letting the couch burn. Jerk.
Isn't the bystander effect great?