A friend of mine told me about running into a man she knew while grocery shopping. She glanced up from the cereal box she was inspecting and saw him reading a bread label a few feet from where she was standing.
She walked up to him and tugged his sleeve.
When he turned politely to engage her she hugged him warmly, asked about his family and stood and chatted with him for thirty minutes.
It wasn't until she was leaving the store that she realized that her only prior contact with the man was morning after morning as he nodded to her when she climbed aboard his bus.