There are so many great ideas here that I forwarded the link to the owner of my LQS, although I love her shop.
Some of the things I love about my LQS:
1. A gift if you spend $100
2. 30% off the color of the monthly birthstone (sometimes for a week/sometimes all month)
3. Weekly 30% off sales in December: notions/Christmas fabric/all fabric
4. 10% off everything when you take a class
5. Affordable classes - usually $20
6. 10% lifetime discount after you spend $1000 in her shop
You may want to set up a video monitor due the all the theft happening these days. Also, you should have people leave large empty totes at the checkout. Theft has been a huge problem in our area lately.