Home is where the heart is, as the saying goes, but the heart of public policy is in anything but housing. We obsess over health care. We go back and forth on the budget. We debate taxes endlessly. But surprisingly little attention is paid to making smarter policies about the places we live and sleep.

That’s why this week’s Working it Out question was: What would you change in your local housing policy? Your comments advocated building denser housing and converting parking spots into housing. What’s my idea?

Well, I was thinking of touting expanded use of pre-fab housing, what’s today called modular housing. Today’s versions aren’t your parents’ prefabs. They’re well, fab.

And because modular homes are stamped out in a factory, they both cost less and are of high quality. Conventional site-based construction requires construction workers rather than industrial machines trying to precisely cut and correctly install all those pieces of wood, sheetrock, pipes, and wire.

I also like the idea of a roommatematch.com. It would be like Match.com for roommates. With today’s lousy economy, it’s not just people just starting out who are willing to live with roommates. For example, there are the four million homeowners who, in just the last four years, have lost their home to foreclosure. (Yes, I’ve just bought roomiematch.net and roomiematch.org. Roommate.com, alas, was unavailable.)

But my favorite idea is to create SuperSublet.com. (Yes, I’ve just bought the domain name.) While they’re at work, millions of people leave their home or apartment vacant, unused, for 12 hours a day. At the same time, countless businesses, from individual counselors to mega-corporations, build or lease space for offices, meeting rooms, classrooms, etc.

Why not pair them up? Here are some advantages:

— Rather than renting or building sterile office space, SuperSublet.com would make it easy for a counselor, corporation, university, etc. to find a more pleasant apartment or home to rent.

— It would likely cost less because the resident had otherwise expected to get zero dollars.

— It’s an unexpected easy source of income for the resident.

— It’s green: less building reduces the carbon footprint.

Of course, there are obstacles. Government would have to relax zoning regulations. Insurance companies would have to offer riders on renters and homeowners policies. And landlords would have to accept the sublessees. Perhaps, just as hotels charge an extra fee for guests with pets, landlords might charge an additional “wear-and-tear” fee for tenants who wish to sublet. That way, your home can be where your heart and your cash cow are.