Think of this as Lego leverage.

The next time you step barefooted on those diabolically cornered building blocks scattered by little Winthrop — even after you warned him — you can just ship it back. After all, it's just a rental.

Using a model similar to Netflix, a California mom has come up with Pleygo (www.pleygo.com), a service that, for a monthly fee starting at $15, lets you "rent" Lego sets. You can build a wish list, order, enjoy, then return the set to trigger the next shipment. Pieces are sanitized between rentals, and the company says it won't charge extra "if normal loss occurs."

The mom, Elina Furman, figured she'd spent about $5,000 on Legos, yet her son always wanted the latest releases. This seemed a way to satisfy his longing while holding down expenses. If renters want to keep a particular set, they can buy it for the retail price.

Lego, based in Denmark, estimates that more than 70 percent of U.S. families own at least one set. Families with languishing Lego sets can offer them to the service, getting credit toward their own rental account.

Word of Pleygo comes as a New Zealand study contends that Lego figures are getting angrier. While most faces still appear happy, researchers found that expressions of anger are more common and more intense. They conclude that "the themes have been increasingly based on conflict."

Could be. But the study also reported a far scarier statistic: On average, there are 75 Lego bricks for every person on Earth.

Or, 37.5 per bare foot.