An interesting list at Cracked tells us about the early versions of some of our modern conveniences, when they weren't so modern or convenient, but that's all a matter of opinion. The oldest of these is a story of how the Cherokee used turtle shells for calendars. It turns out that a turtle shell has 13 segments on the inside, and 28 segments on the outside. That corresponds well to 13 lunar cycles in a year, and 28 days in each lunar cycle.
A First Nations legend describes how the unassuming turtle received its divine temporal cognizance. Many moons ago, long before Creator peopled the Earth, the animals could talk. One day, Turtle and Raven exchanged pleasantries, and Turtle, lamenting his terrestrial limitations, wished to taste some of that sweet sky for himself.
So Turtle bit onto a twig, and Raven lifted him high into the heavens. But when Turtle opened his mouth to express his pleasure, he fell to the ground and shattered his shell. Creator took pity on Turtle and put its shell back together with the purpose of tracking the moons. Creator also bestowed long life on Turtle and made it the Keeper of Knowledge.
Read the rest of that story, plus four others at Cracked.
(Image credit: Pierre5018)