Partner with schools or professors to have students buy school texts only available at your store.
Reconfigure your space to include a living quarters for visiting lecturers or artists. Have them earn their keep by leading discussions or giving a reading.
Have a large used and new graphic novel section. Buy used graphic novels at 33% cost or 50% credit.
Organize your bookshelves using the Library of Congress Classification System.
Get a housecat, name it something amazingly cute, the tweet advertisement for sales from POV of the cat using funny catspeak.
Invest in an outside sitting area or patio style backyard.
Rent out half of your store space to the United States Post Office.