Google's Project Sunroof wants to put solar panels on your house
Enter your address at Project Sunroof and Google, using Google Maps, will calculate how much sunlight your roof gets in a year (taking into account shadows from nearby structures and trees as well as a 3D modeling of your roof) and estimate how much energy you could save. Project Sunroof will recommend an installation size and also suggest solar providers in your area.
Unfortunately, as Android Police points out, the service is currently available only in limited areas in the US: Boston, San Francisco, and Fresno. However, you can put in your zip code and your email address to be notified when it comes to your area.
Hopefully, it will be soon--before the end of 2016, at least, when the federal incentives will expire. As I wrote in my post on Lifehacker about solar panels, the federal subsidies cut the cost of a solar panel system by 30% and you can save $6,000 or so (on an average $21,400 system) through these credits, on top of the savings on your electric bill.
I've been thinking about going solar myself, so hurry up Google and bring Project Sunroof to us all.