I was playing scribblenauts on the DS.
Now, Ds1 has never seen this game before, and for those who don't know, it's a game where you add objects to your situation to solve a puzzle or conundrum.
So... I was trying to figure out a way of stopping bombs falling across a path I was trying to cross, and was messing about rigging up invincible slides, putting wings on my character etc etc.
Ds1 peered over my shoulder and announced "You need to put a roof there"
"Well I can't" I snapped peevishly. "A roof would fall down without something to hold it up, wouldn't it and if I put something there to hold it up, I can't cross the path"
He looked at me as if I was the stupidest person he had ever spoken to, then sighed and said, "Use a static roof. Static means it doesn't move. You told me that when we stayed in a static caravan, Mummy."
Now, I always had myself down as a relatively bright person with a good vocabulary, and I've just been whupped by an 8 year old.