It looks like a lot of folks are on a mission to put stock photography websites out of business. We published an article a while back showcasing five free stock photography, but more and more have popped up since. Some are not so great while others are fantastic.
Pexels.com is a new stock photography site that has over a thousand free stock photos that you can do whatever you want with. All of them are licensed under Creative Commons Zero (CC0) which means you can copy, modify, distribute and even use them commercially. No attribution is required.
The site itself is very well designed and the photos are very high quality. The one you see above is from the site. Most of the images are also very high resolution so they're perfect for retina displays too.