If watching the 2010 World Cup from South Africa has inspired you to set up a soccer goal at home, there's an alternative to store-bought goals. Developed by Steve Klein, a former New York City schoolteacher, the Eco-Connect Bottle System is intended to be a green, inexpensive way to make a soccer goal (a computer-generated version of the goal is shown) out of empty, used plastic soda bottles. The Eco-Connect system, hopes Klein, could also be used for toys and building materials.

The Eco-Connect Bottle System puts a threaded indentation on the bottom of the plastic bottles, allowing you to make a goal by screwing the bottles together. You connect the goalposts, crossbar, and other legs using a series of connectors. (Read this important safety advice about soccer goals from the Consumer Reports Safety blog.)