So far, this is the only vertical doodle I've done. I tend to prefer the horizontal format, except for this one.
This doodle is done in green ink on bristol board.
Standard ACEO size: 2.5 x 3.5. Card is an original and signed on the back.
My ACEOs -- doodles, collages, and paintings -- are now available through eBay: http://shop.ebay.com/lifeneedsart/m.html