If you sign up for the enewsletter from East Side Marios, they'll email you a printable coupon for a free appetizer!
The coupon that I received was valid to the 31st December 2011, and it's unique to me so I cannot share it here. You'd need to sign up at the above link yourself. I received the email with the free appetizer a few hours after I signed up, so it shouldn't take long for your coupon to come through.
Terms:
Prices may vary by region. Dine-in only. Taxes extra.
It says you just have to buy any entrée to get your free appetizer.
P.S. There's an East Side Marios coupon for $10 off $30 until the end of June 2011, if you'd prefer to use that.
