You've heard of baseball cards, but do you know about artist trading cards (ATCs)? They are artist-made miniature works of art to collect and trade. Collecting ATCs is a popular trend right now. (An internet search of "artist trading cards" + "your city of choice" will yield information on local groups that meet to trade cards.)
Along those lines but on a larger scale, the publishers of the art magazine, Kolaj, have begun issuing packs of 15 Collage Artist Trading Cards. Their goal is to further disseminate the work of contemporary fine art collage artists and to encourage people to learn about new artists. These are professionally printed cards, each measuring 5.5 x 3.5" with an image on the front and information about the collage and the artist on the back.I'm happy to be included in Pack One of the trading cards (issued late 2013) along with international collage artists Bev Butkow, Ewan Aparicio, Holly Savas, Jeni Bate, Joe Castro, Kamee Abrahamian, Lita Kenyon, Mongobi-Bibbiana Mele, Nikki Soppelsa, Pierre-Paul Pariseau, Ross Carron, Sara Winkler, Stephen Tierney, and Vesna Vrdoljak.
If you'd like to start a collection of your own, the cards are available for $10/pack here from Maison Kasini.