I am having a lot of fun making and swapping atcs. It is satisfying to have a way to use of all the odds and ends of recycled things that I have been saving too! I have it bad - I just don't like to throw things away that could serve some crafty purpose. Today I ran across a great use for recycled envelopes...bookmarks at Go Make Something.
There is a wonderful tutorial. Basically, you cut off a corner of an envelope and then decorate it like you would an atc. It forms a pocket that can fit over the top corner of a book page to mark your place. What a great idea!