Let's get kids out of Google Images and into Good, Free, Legal Photos

I echo Grumpy Old Teacher's sentiments exactly when he says:

Again I say, let's get our students (and colleagues) to stop using
Google Images, and get some real quality images into their work!

Amen to that, grumpy!

Suggestions, including one new one:

1. Every Stock Photo -- Free search Engine for stock photos including the ability to critique and share your photos.  What a great idea. (from Grumpy)
   
2. Flickr Storm - (Also from Grumpy)
   
3. Creative Commons Search - I've been using the built in creative commons searches in Firefox to find ours. (This is what we use.)
   

What are your places for good, high quality, free photos?