$1 for $400 Off Home Solar Power from SolarCity Coupon

SolarCity has found that when you make a solar power system as free as the sunshine that fuels it, people notice. By removing the biggest roadblock for most people—installation of the panels is free, so you only pay for the power they generate—SolarCity estimates that it converts a new person to solar energy every three minutes. Walmart, eBay, and Intel have also taken notice; they're a few of SolarCity's business clients. Fortune recently ranked SolarCity's founders No. 3 on its list of The World's Top 25 Eco-Innovators (its chairman, Elon Musk, was No. 1), and the Stevie Awards presented the company with a gold award for its customer service.