I used to have a great collection of the original MOTU toys as a little kid.
My mum and dad still laugh about this story:
It was the night before my birthday (I was about 5 maybe?) and my folks were assembling the Castle Greyskull they had bought me and I walked into their bedroom...the look on my face said "so THIS is what you do once I've gone to bed!"
They had to let me stay up and play with it