I blink whenever I'm counting those white dotted lines on highways.

If I'm looking at an object, such as a countertop or a garage door opener, I imagine what it would be like if I were tiny and lived on that spot for my life, just to see the perspective from it.

I count stairs every time.

I ALWAYS keep a pair of chopsticks in my car, so if I'm in traffic, I drum out to a song while I'm crawling along.

When I'm walking down a hallway, and I don't want to say hi to some stranger (company policy), I look up at the ceiling in an interested way. Sometimes they look, too.

When I'm eating something crumbly, I rub my index and middle fingers against my thumbs briskly until ALL of the crumbs are off. I do this with kief, too. But I save the kief

For other oddies and nonsense, read my "Synesthetes Unite!" thread... :P