Flickr Commons contains a vast array of free-to-use public domain images from many collections, well tagged and annotated.
In general, I prefer Wikimedia Commons (http://commons.wikimedia.org) though it is slightly harder to find public domain images there (many are CC-licenced) and the consistency is not as good.
I am a professional learner, employed as a Full Professor at Athabasca University, where I research lots of things broadly in the area of learning and technology, and I teach mainly in the School of Computing & Information Systems, of which I am the former Chair.
I am married, with two grown-up children, and live in beautiful Vancouver.
