Thought I'd try a zentangle as I've heard about them a lot, and presume they may have the same meditative effects as mandalas, which as you may know I love. I'm not too sure what the 'rules' or conventions are, but I think you draw a random shape, break it up into several smaller random shapes, then fill each shape with doodles. Also that they are usually worked in black and white. Or at least, these are the guidelines I'm using, and so far it's looking promising. Can't wait to see how it progresses.