There's an awesome art community on the Vine app called "We Draw" that has artists posting art every week based on a picked topic. I usually try to participate when I can (or when I'm not overworked) but there are some really great artists I've been introduced to like Heather Mahler, Mark Pingriff, and a slew of others. If you have time just go through their timeline. It's a great experience. Here are some of the sketches I've done for We Draw over the months.