I live near a busy intersection. Most people keep walking. I see the same man who walks home while he's drunk. He vomits a lot near my corner. The strangest thing I've seen near the corner was a man who stood near the corner. He lifted up his shirt to twist his nipples. Perhaps he has an issue and he doesn't realize that he does that. I only saw him once. I was driving home getting ready to turn onto my street when I saw him. It was good thing that my pick-up truck has the technology to stop itself. I would have been very embarrassed to have hit the car in front of me.
I've wracked my brain trying to remember when I last noticed something strange, new or surprising. It would have to go back to when I was very young and still didn't know much of the wider world. I remember the first times I saw a homeless person sleeping on a park bench, a busker, a schizophrenic having a psychotic episode, a spruiker, a Scientology questionaire-er, a charity collector, someone with an odd pet like an exotic parrot or snake, someone dressed up as a koala... and so on. But soon, none of those things were strange to me; they're just another aspect of life - sometimes sad and wrong, other times joyous and fun, but still a part of the total reality.