Every time I pass a colleague walking the other direction at work there is one of four reactions:
1. Look straight ahead without even acknowledging the other's existence.
2. Look straight ahead and then suddenly look down at the last second to avoid any chance of eye contact.
3. Look at the other person and then look away as soon as the other starts to glance over for eye contact.
4. Make eye contact and smile, possibly saying "hey". This is also sometimes followed by looking down at the ground as if to give the person a bit of thrust in the direction of walking to make the encounter even more brief.
While I understand that passing people in the hallway is a very frequent thing and niceties get old fast, I can't help but feel a bit slighted when these reactions happen all the time.
How do you react in this situation?