Answering questions all day, such as "What's 40 plus 100?" and "Do you like the number zeeeee-ro?" (Answer: no. Why? Because there's nothing to it!)
Understanding that sometimes you have to give a little extra time to get an answer, or ignore words that seem to slip out in frustration.
Time. I never have to worry about not knowing what time it is, ever again. I just ask my walking scheduler; and if we miss an important time, we hear about it.
Interesting pretend play- mixes of scripts from shows, movies, games, even books, stitched together to create new scenarios. He's being Buzz Lightyear and Scud at the same time, while watching out for the snappity-snap fish, using teamwork.
Small things done in great ways- such as having little fingers eagerly buttoning my coat, that first time he came up the stairs and called me Mommy, that first point across the room at a pumpkin. The pride he takes him his accomplishments, in meeting his challenges, in knowing he is moving forward.
Making the world around him smile, because he just beams his joy in being. Joey loves everybody, and makes sure they know it.