i guess i should explain what an atc is since i am so addicted to them lately. atc stands for artist trading card. it's a 2 1/2 x 3 1/2 inch piece of artwork. people make them and then trade them (kinda like baseball cards!). anything goes with an atc as far as what type of material to use, the only real rule is that it is always the same size and you aren't supposed to sell them. the artist creates the design on the front, then signs the back with their name, title of atc, contact info and number of atc (usually 1/9, 2/9, etc. with 9 being how many were made). the atcs i make usually have a theme and are swapped out between a group of people so each person has a collection of 9 atcs. i put my atcs in baseball card sheet protectors and have them stored in binders. it's fun to look through them and get ideas for cards or other atcs, or just to browse! they are fun, make you think outside the box to get something to fit on the small size, and certainly addicting!