Over at i am neurotic:
If I accidently tap my pinky on a table, that’s ONE, and I must complete a 100-count: the four fingers left on one hand (5), the five fingers on the other hand (10), then 10 fingers together (20) and again (30), and so on until 100.
When I am riding in a car, I imagine lines going out from the corners of the car to the edge of the road, enclosing a certain region of the sidewalk. Whenever something like a tree or a car falls within this region, I have to register it, often by clicking my teeth. Also, the things I register have to alternate sides.
Any texture that involves networks of tiny lines crossing at random angles (such as the vein-skeleton of a decayed leaf, or projections of eye capillaries) drives a cold chill up my spine. Tiny networks of straight lines (like mosquito netting) are fine.