Fun Letter Writing from a Cat's Point of View

I had my kids at school write a letter to my daughter pretending they were my daughter's cat, Muffassa.  I showed them the video she made about her cat, some pictures of him dressed up in her baby clothes & told them a few stories about Muffassa.  I call him Maximus because he's so huge! 
We also read a bunch of picture books that had letter writing included & discussed how letters could be used to tell a story.  These are some of the books we read:
I Wanna Iguana

Yours Truly Goldilocks

Dear Mr. Blueberry

Dear Mrs. LaRue:  Letters from Obedience School

Dear Juno

and With Love, Little Red Hen

Dear Peter Rabbit

They loved pretending that they were such a bad kitty & loved making demands on my daughter to do this & to do that for them.  It was a great introduction to letter writing for them.  They used wonderful 'show me sentences' and let my daughter really know how they felt about her not cleaning their litterboxes on time & what they thought about her food choices and the like.
It was a great lesson & I just thought I'd share.
What was your favorite lesson of all time - either by you or from a favorite teacher you had?

Here's the youtube link that I showed my kids of Muffassa:
http://www.youtube.com/watch?v=z0yVBaF6eC0&feature=related