I did not think that Bill Watterson drew some of the panels in PEARLS BEFORE SWINE this week.
I was wrong.
Stephan Pastis tells the whole story at his blog: Ever Wished That Calvin and Hobbes Creator Bill Watterson Would Return to the Comics Page? Well, He Just Did.
It was, as he says, the hardest secret he ever had to keep.
The whole story of how it all happened: how he approached Bill Watterson, how the strips came to be, etc. are all there.
Hat tip to Charles Brubaker for the heads up.