Making shapes out of clouds is a great pastime. But I've discovered a modified version for all you travelers.
When flying into a small city at night (or butt-crack-of-dawn), you can make amazing shapes out of neighborhood and street lights. This morning I saw an astronaut, an umbrella and a person sticking their tongue out.
Pretty sure this doesn't work flying into the sprawl that is LA, but cities with a little more green space, it most definitely works.