Quiltworks, that is a very interesting marketing tool. What if, instead of business cards, you enclose a printed sheet (Small like a bag stuffer people use at stores and craft/art shows. We used to get 4 bag stuffers from one sheet of printing paper, plus we used differnt colored sheets for differnt seasons.)that says something like this:
"Thank you for purchasing my artwork. I've included a list of other artists you may be interested in.
1. Kim Loberg, purplehorse75 @ eBay, account info
website etc. (or what ever info you wish to include and maybe the type of artwork your known for).
2. etc."
A small printed sheet would be cheaper and less bulky for mailing than business cards and easier to edit as information changes. A very small icon of the artist's artwork could even be added to the flyer so the buyer could see the actual artwork.
Kim