I've recently started playing with Zentangles after a Facebook friend introduced me to this type of doodling art. Technically, zentangles shouldn't have any realistic shape or form, just patterns, but I find these to be more fun and can display a specific theme. This one of a jockey on a horse I did for friends of ours that throw great Derby parties every year and have a Derby themed living room in their house. This is the first one I've done with a theme, so I'm happy with how it turned out. I hope to do many more to add to my collection! I'd like to play around some more with themed tangles and also try some in color.
To learn more about Zentangle and Zentangle patterns, check out Zentangle.com and Tangle Patterns. Or check out some really cool Zentangle galleries from Flickr's Zentangle Mania Group or my Zentangle PInterest board.