Calvin and Hobbes by Charles Santoso. I took the liberty of turning it into a widescreen desktop wallpaper:
Charles has several adorable monster prints on sale for $30 each here.
As I mentioned last month, he was scheduled to be interviewed by Bobby Chiu at sketchaholic, and give away an illustration to whoever best depicted the theme "nocturnal." (He was a concept artist on Legend of the Guardians: The Owls of Ga'Hoole (the armored owl movie).) Here are my favorites from those submissions. The first was the winner:
*Buy Calvin and Hobbes stickers at Amazon.