These small canvas panels are difficult to find in Brussels so I ordered them at www.SharksArtCanvas.com. I have been calling them ATCs ("Artist Trading Cards") but it looks like that is used only for a specific exchange project. So the generic term must be ACEO ("Art Cards, Editions and Originals").
First, I finally got around to doing the Daily Paintworks painting challenge from 2011. Take a look at the site to see all the cats:
The whole cat and kaboodle challenge
6.4x8.9cm, oil on canvas panel
After that I tried Evhe's "défi de peinture", which I just discovered last week. I am amazed that by checking the VPO blog in Kentucky, I linked to a blog in Malaga and that's where I found a link to this painting challenge hosted by a painter in Moselle:
A nos pinceaux
ACEO n°7: "Tulips"
8.9x6.4cm, oil on canvas panel
(Private collection, Brussels)