I'll start with one that really sticks out to me- George Lucas always directs actors with belts on to put both of their hands on their belt. Obi-Wan does it, Darth Vader does it, Count Dooku does it in the arena in II- even look at the deleted Jabba the Hutt scene from SW- Jabba does it. Palpatine does it several times in the PT. It would be a coincidence did it not happen so many times when he directed.
Any others?