My sister-in-law is the librarian for a large, private school in Los Angeles. Her library is a sunny, friendly space with a lot of attractive book displays and fun decorating ideas.
The library had two huge air-conditioning ducts that couldn't be hidden, so look at this clever solution:
The ducts were painted to resemble two adorable bookworms!
And their names are Google and Dewey (for the Dewey Decimal System.)