....a day without air.
I wish I had invented velcro first. Contrary to popular belief, NASA did not invent this revolutionary 'material'. Click here to read about the history of the stuff.
Here's a micrograph of velcro...pretty cool huh?
By Natural Philo (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons