First there was co-housing, where people got together and built intentional communities based on sharing resources and interests. Then there was co-working, which brought the so-called sharing economy to the workplace: a pay-as-you-go for as-long-as-you-need workspace. Now there's a new co-kid on the block: co-living. It’s not just a remake of "Friends," where people are sharing an apartment; in co-living, it's a business, with professional management operating the space and offering it on a month-to-month basis. They offer laundry facilities, maid service and even Nest thermostats.

It also could become a big business, with a couple of startups offering space in hot cities like San Francisco, New York and London, where conventional housing is expensive, hard to find and often does not meet the needs of people today. As Brad Hargreaves of Common, a New York startup, notes in Inc:

Being able to live anywhere, rather than being bound by yearlong leases in individual cities and individual buildings, really reflects how people are living and working today. We’re not committing to one career for all 40 years of our working lives. We’re switching between jobs, between gigs, between traditional and nontraditional education, between startups. And we want to build a type of housing that enables that.

couch in commonA curated couch in Common's co-living living room. (Photo: Common)

Hargreaves just opened a building in Crown Heights, in trendy Brooklyn. “Designed to make daily living comfortable and enjoyable, this Common residence has everything you need to feel at home.” It includes a private rooftop and garden. The interior isn’t designed, it’s curated. It’s also an instant success, with 300 people applying to get one of the 19 bedrooms in the building.

The always snarky Gawker thinks it's a terrible idea, given that one can rent a studio apartment for the price of a bedroom here. They call the $1,800 rent:

Quite a deal! Of course, if you took the traditional, outmoded route of just renting your own apartment, you would miss out not only on the chance to meet 18 new people who you would soon grow to hate, but also the chance to be a part of this Common Living startup’s plan to “build bridges into and relationships with the existing community that lives, works, and plays in Crown Heights.”

They have a point. One could look at this and note that it's really just an upscale rooming house, another way for developers to squeeze more money out of a property, renting by the room. In San Francisco, one company has been getting into trouble for converting hotels that served low-income people into "digerati dorms" for rich tech workers while not meeting municipal standards.

But there's a real need being met here. Fast Company’s Sarah Kessler writes about how renting an apartment isn’t so easy in New York, where the landlords want to see two years of tax returns and proof that the renter earns at least 40 times the rent, or about $100,000 a year in New York. She tried co-living for six months in another startup’s property, run by Campus, partly funded by Paypal cofounder Peter Thiel. Her house turned into a sort of yuppie commune.

We become a house of nerds. We watch "Good Will Hunting" together and talk about the math. A small group decides to set goals every week — things like practicing extemporaneous speaking or studying German phrases — and if everyone meets them, they go out for pie together.

But Kessler finds that it begins to get on her nerves, so much sharing. She can’t go to the bathroom without having to make small talk. And eventually she has to leave, because Campus went bust; one of its problems was that it let tenants interview and reject other potential tenants, leaving rooms unfilled.

collective baseThe Collective: You get a crash pad up top, and your living room is in the base. (Photo: the Collective)

But that has not stopped others from having even grander, and perhaps more business-like visions. In London, The Collective operates a number of properties and is proposing an 11-story building with 550 rooms. As its 23-year-old CEO notes in the Financial Times, young people travel light and don’t need so much space: “My parents have a bookcase full of books and DVDs; I have a Netflix account and a Kindle. We’re far more experience-based and less possession-based.”

CommonspaceCommonspace: A teensy apartment with a big common area. (Photo: Commonspace)

In Syracuse, New York — not exactly a hotbed of activity like London — Commonspace is offering an interesting mix of public and private. It’s a conversion of an office building and an attempt at revitalizing a Rust Belt city’s downtown. Tenants get a micro-apartment that includes a tiny kitchenette and private bathroom, but just outside your apartment door, there's a large common living area and a big communal kitchen. This is perhaps the best compromise — 300 square feet of private space with optional shared resources. That’s how the original co-housing model worked, giving people a choice.

It’s interesting that all of these co-living projects are aimed at millennials looking for “hip housing on demand.” There's probably a bigger and wealthier audience of older singles who would probably love “communal living for grown-ups.” Forget the Yuppie Commune, we want a Boomer Commune.

Lloyd Alter ( @lloydalter ) writes about smart (and dumb) tech with a side of design and a dash of boomer angst.