Bunk Bed
I spent my childhood sleeping in a bunk bed with my older brother. Because he was older, he had dibs on the top. We used to try to parachute out of the top bunk using green plastic garbage bags. Downstairs in the kitchen mom shouted up, "Cut that out! If you want to play go outside!" I still think they're cool beds and very practical for a certain demographic.
The parachuting idea didn't go. We only dislodged light fixtures from the ground floor ceiling. So then we went to the local public school playground and tried jumping out of the lowest branch of a tree - a tree that still stands today. That didn't go, either. After that we pretty much abandoned the parachuting idea.