Instructables member peinkc spent only $15 building this portable fire pit. After removing the interior rubber and plastic components from the shopping cart that he legally acquired, he built a bottom pan out of cookies sheets and fitted mesh spark screens along the sides and top. The bottom rack provides a convenient place to store logs.
Actually, if you go to the original link (above), you'll see he did NOT steal the cart.
John should edit his post so people can enjoy the project without assuming the cart was stolen property.