The concept has not entered the commercial mainstream yet, though.
"The e-book industry has not hit the mainstream yet.
Africa's success story is finally becoming mainstream – yet sustained growth is not inevitable.
"African literature is not properly in the British mainstream yet," says Arac de Nyeko.
We know this because three of the decade's biggest mainstream yet seminal bands are back.
But it's far from mainstream yet and it needs to be.
These have understandably been subject to a gamut of robust approvals, and so haven't hit the mainstream yet.
"It hasn't got into the mainstream yet," says Ken Guthrie, who chairs the International Energy Agency's Solar Heating and Cooling Program.
"Divestment, while spreading wildly, isn't mainstream – yet," says Leslie Samuelrich, the president of Green Century Capital Management and a divestment advocate.
G.M. has nailed it, creating a hatchback that feels peppy and mainstream yet can sip less fuel than any gas- or diesel-powered car sold in America.
