- Playing with my chin/beard while thinking.
- Washing my hands & face rather frequently.
- Sometimes I have to do something over until I get it right. It used to be worse for me years ago, e.g. I would have to arrange something so that it's to my liking, such as arranging objects in a room.
- When coding, compulsively adhere to proper syntax (a good thing about being OCD ;-)
- Perfectionism.
- I get annoyed when reading improper grammar (such as your post uuntiltheendd). I mean, at least capitalize personal pronouns, for fuck's sake!

I can't really think right now because my sleep cycle is messed up.