I participated in an event put on my the Arthouse Co-op called the Sketchbook Project 2012. My submission has been added to their Online Library and is now viewable at the above link.
They sent me this little blank sketchbook and a theme (you can choose the theme from a list, or have one assigned randomly - I opted for the random selection option) and you just fill it up however you want and send it back to them, to be added to their collection, which tours the world.
The theme I got was 'Writing on the Wall'. I looked up the expression and found it comes from the Old Testament, from the story of the Feast of Belshazzar, who was the last king of Babylon.
The story goes like this: Belshazzar had come into possession of some treasures looted from the Temple of Solomon, and was using them during one of his ritual feasts, honoring some heathen god. This displeased God so he sent a warning to Belshazzar; a ghostly hand appeared out of swirling vapors and wrote these words on the wall: Mene Mene Tekel Upharsin. More or less, that means 'Your Days are Numbered'. Belshazzar was like 'whatever, man' and he kept on feasting. Next day Babylon was conquered by the Persians, and his kingdom was no more, erased from the earth forever.
Not a bad story I guess. My sketchbook reflects my own personal perspective on those themes.