Jax Kar Wash offers a free wash on your birthday if you are part of their frequent users club, otherwise, they will charge you a dollar (or just ask for an exterior wash only.
Found out yesterday, that Seva Restaurant (Ann Arbor and now in Detroit) offers the birthday person a free entrée on his/her birthday.
If you register your Starbucks card online, you will get a postcard in the mail for a free beverage around your birthday.
Noodles & Co. sends an email noodlegram a week before your birthday for a free bowl of noodles around your birthday.
Office Max sent me a $15 off (a $75 online order).
Olga's Kitchen sent a printable coupon for a free dessert to use within 30 days of my birthday.
Buddy's Pizzeria sent a printable coupon for a free 4 slice pizza (or the value towards an 8 slice pizza). Dine in only and you need to choose your location when you sign up for emails. Buddy's is so cool, that I entered a Facebook Sweepstakes and won a 1 year family membership to The Henry Ford (museum) and Greenfield Village!!!
Here is a link to a huge list of other birthday freebies (I did not verify them).
Remember to register early and often!