Post Cards, made to a set size (6 x 4") can be easily posted, with or without an envelope. I have been sending these out as exchange trades with other artists, as well as selling them at exhibitions.
ATCs Art cards are even smaller at 2.5 x 3.5 ".
Based on earlier sports fan trading cards, Art Trading Cards (ATCs) are swapped, not sold. They were started in 1997 when Zurich based artist Vänçi Stirnemann exhibited his hand made cards in Switzerland. Visitors were encouraged to trade cards they had produced. The rest is history, as art makers joined in on the Internet to trade world wide. Here are some of the many cards I have made in the last year.