If you do any kind of work on the web (or off the web) that requires high quality photography you probably know about Unsplash.com. If you don’t know, you’re welcome.
Many folks will use the photos for blog posts (this guy), or similar places online, but there’s a cool website dedicated to all the ways people have used photos from Unsplash.
The site started a few years ago as a side project by a company called Crew, and now has over a million photos on it.