Artregards is a curated art site that offers something a bit different. If you are an artist you may apply to join. Once accepted you upload your art. Your art images may then be purchased on the front of e-cards that allow personalized messages to be added inside on the Artregards site. You the artist receive a share of the purchase price for each e-card that goes out with your art on it.
This is a very simple type of art licensing. Artists hold all rights to their art and may cancel the license with Artregards at any time.