The monkey represents sharing.

From an IM conversation between me and my wife several weeks ago:

Me:You can get me this t-shirt for my birthday.
Her: A monkey riding a pig? Really? You want that tshirt? Of course you do. What am I thinking...
Me: It's a monkey. Riding a pig. Who wouldn't want that shirt? Plus, I remember fondly the bad mojo that pig riding monkey worked on the Tinkle Family.

Well, my birthday wish is coming true. Not only will that bad monkey ride that pig into my wardrobe, but guess who's getting a WIGU Vol. 1 book made out to me with a sketch by Mr. Jeff Rowland? That's right, me. Yay! Yay! Yay!

My wife rocks.