I did this in response to the Drawing Lab group's week number 5, based on Carla Sonheim's book. Sharpie marker and watercolours on 5 x 7 watercolour paper.
It's not too late to join, all you need is the book, I've been having a lot of fun with the exercises so far, it's helping me to step out of my normal box of tools and way of looking at things. There is plenty more to see in the Flickr group too. Lots of inspiration!