Before I go any further ACEO stands for Art Cards, Editions and Originals. The only stipulation is that they are artworks of 2.5" x 3.5" in size - miniature art basically. After a brief foray on Etsy, I decided I had to order a couple to start off my new-found collection of affordable artwork. I'm planning to store my ACEOs in a nice decorative box so that I can browse through them at any time - like having a little tour around an Art Gallery, without having to leave home! My own little stash of art work - all mine - Muhahaha!! Enough of the evil laughter, I'd better sell these 'beach-balls' below which I eventually completed yesterday, if I'm going to fund my new hobby!
P.S. You can buy ACEOs for as little as £4 ($6) upwards to £20($35) or more (try Etsy), depending upon the artist, intricacy of the piece, quality of artwork, etc. They are available in all mediums - oil, watercolour, textile, embroidery, mixed media, etc. Also limited edition prints, which I personally don't find so appealing. (ACEO producers can correct me on any of this info if it's not quite right!)
P.P.S. That nice lady from Cuteable has a lovely blog specifically about ACEOs here! What a lovely idea they are and quite kind to your wallet too - affordable original art, what's not to love!! I'd better get crafting!