While searching for some technical information on a computer forum recently, I happened upon a very interesting online drawing app ... a randomly found link wouldn't usually be considered for this blog, but I couldn't resist in this case, since it's called Harmony. :-)
Check it out here: http://mrdoob.com/projects/harmony/
If you're the artistic type, you'll be able to create amazing things with the very interesting brushes available and the configurable background and brush colours ; if you're just a doodler (like me), this will be some of the most fun doodling you'll come across! You can save your creations, too - check out the options in the menu at the top of the page, and enjoy some Harmony!