When word got out about Amazon Flex, it wasn't clear exactly how it worked. Was it a pick-it-up-yourself service? Not really, as it turns out. The online retailer has finally taken the wraps off of Flex, and it's ultimately an Uber-like service that has on-demand contractors delivering your Prime Now orders. Like with ridesharing, couriers have to bring their own car and install an app on their phone that notifies them of gigs -- the difference, of course, is that they're transporting packages instead of people. Recruits make between $18 to $25 per hour, and they can work as much as they want.