The World Usability Day (WUD) project will make 1,000 LED spot/bulbs available for free via their website www.worldusabilityday.org. "Assume the following math: 1,000 bulbs can replace all of the light bulbs in 20 medium-sized houses," said Brian Sullivan, the usability principal at the Sabre Human Factors Center in San Francisco, CA, and co-chair of World Usability Day. "The LED bulbs are easily three times more efficient than standard bulbs. So that is the equivalent of lighting 100 houses," said Brian Sullivan, co-chair of World Usability Day.