Fiverr ($FIVERR), the online marketplace for freelance services, has come a long way since it was founded in 2010. At first, it invited freelancers to offer their services for $5 a pop, and would-be employers looking to outsource for small jobs flocked to the site.

Fiverr is one of several players in the space, along with TaskRabbit, Freelancer, Mechanical Turk, and UpWork. They've all scaled, diversified, and grown. According to Dr. Otto Kässi, a labor economist and researcher at the Oxford Internet Institute in the UK, the future of work looks a lot like the gig economy that these services suggest. "We do observe a substantial year-to-year growth in the demand for online labor as a whole (see this Online Labor Index), with over 30% yearly growth rates," he said.