If you're a fan of Jack Astor's, you'll definitely want to sign up for their VIP Club. In return, you'll get a coupon good for $10 off your next visit! You have to supply your name, email address and birthday to take part, and there's an option to supply a cell phone number to receive SMS offers as well.
The coupon is valid on food and non-alcoholic beverage orders over $25, and there's a limit of one coupon per table. The coupon will expire 15 days after it is emailed to you.