"Can't draw"- it doesn't matter, just find a pen, the kids crayons, your lipstick, anything goes, just have a play and remember how much fun it was to draw when you were a child.
If you already draw then try a completely different style, or start that project you have been putting off because something else always seems to come up.
Get the kids involved or get a few friends around and have fun with it.
For those feeling brave then you can upload your work to their website and show the world your wonderful creation(s). It could possibly even make it into a book the organisers are producing.
I am planning to set my kids up with some big sheets of paper and a variety of supplies so they can do some mixed medium drawings. As for myself, I plan to do a work I have been putting off for ages as it is so completely different to anything I have ever done. I can't wait ;-)