Demand is growing rapidly for homes in walkable areas, where it's not a given that a one-ton automobile is required to get one dozen eggs from the store. But how does one go about finding out just how "walkable" is that new home or apartment?After Seattle residents Matt Lerner, Jesse Kocher, and Mike Mathieu saw a group of static walkability maps in Sightline's 2006 Cascadia Scorecard, they had a brainstorm, and in Matt's words, "realized we could make an engaging interactive version instead." Though newbies to the realm of planning or design, they knew technology, and after "a few weeks of work," they had produced Walk Score. Measuring your score is as easy as entering your address, clicking "go", and watching as the points add up. According to Lerner, the score comes from an algorithm that measures distance to amenities, but also "for each category of location (e.g. grocery store, restaurant, coffee shop) we assign a score based on the closest result," said Lerner. While the system may not be perfect, due to the difficulty of measuring many of the factors that make walking possible and attractive, it does perfectly illustrate the massive, unmet demand for neighborhoods where driving is simply one of many options. "Walking isn't just good for your health, it's good for the health of our neighborhoods and the planet," says Matt Lerner.