Or "50k new firms each with 20 employees". When I first read the OP I thought about some new "Green Power" innovation where you need installers, servicers, etc. Possibly-crazy example would be PV that's 100x cheaper / more efficient than today, leading to an explosion in the demand for rooftop installations -- to the level of nearly every household, strip mall, big box, etc in the developed world. Prior example might be the auto industry 100 years ago, which created a need for parts mfg firms, dealers, mechanics, etc.
Or an entirely new and previously unheard of industry. Definitely-crazy example would be making Mars colonization possible, where you'd need thousands of employees for production, thousands more colonists, specialists like pilots, entire sub-industries, etc. The canonical prior example would be the explosive growth of the internet over the past 30 years; SEO as a job title (to pick one) didn't exist in 1990.
Pneumatic transit comes to mind. Demonstrating the viability of Hyperloop as the first new mode of transportation since the jet would spurn a whole new global industry practically overnight!
Ohwait.
No, it actually doesn't work. While it does sound like a good idea in theory (tit-for-tat), in practice greedy corporations (I mean that neutrally, in the capitalist sense where corporations have a duty to extract maximum profits) have powerful incentives to shaft employees over these benefits in order to maximise shareholder value.
In an ideal scenario, companies would compete for employees, and would provide good benefits to out-offer other companies. In practice, a large part of the workforce is groveling for jobs and will accept any raw deal for some kind of income.
Oh hey, egregious example: Walmart http://en.wikipedia.org/wiki/Criticism_of_Walmart#Health_ins...
Or that thing that's been in the news lately: http://america.aljazeera.com/articles/2014/6/30/hobby-lobby-...
Or some random link from "company denies healthcare news" search: http://www.news-leader.com/story/money/2014/03/18/washington...
Such a company might not be feasible in the current regulatory climate, but some people say the same about Uber.