I just joined the ACEO Street Team on Etsy, called ACETSY. They are a very talented group of artists who enjoy creating those mini pieces of art that are referred to as ACEOs. They can be created in any media, the only "rule" is that they measure the standard 2 1/2" x 3 1/2"--the same size as a baseball card.
They have a blog that I have just begun to follow where they share information and post some of their work. Check it out if you are interested in joining or collecting aceos.
Here is my latest ACEO which I created for a challenge hosted by one of the Team members, Jocelyn Friis. The challenge was to create a piece to fit the theme, "Peace Starts With A Smile". Most anything in nature gives me a peaceful feeling, so I created this watercolor of irises. You can read more about the challenge, here, and check out the wonderful prize she is offering! You may just decide to enter for yourself!