The only time I could ever be considered obsessive/compulsive is when I play games. If my items aren't in stacks with a multiple of five, I go out of my way to buy/sell/drop said items to make it so.
With my money as well, I always stick all my ones together, then my fives, then the tens and so on and so forth. Anything else though, I couldn't care less. My mom on the other hand...