Something I haven't seen talked about (or maybe I just missed it) is Birthday Email Clubs. They have been a great upsell for me so I wanted to pass along that idea if others haven't thought about offering them before.
I work with alot of businesses who are looking for ways to turn customers in to repeat customers (restaurants, salons, boutiques), so setting up a mailing list is a no brainer. Once they are sold on the mailing list it's an easy upsell to get them to spend more to include a Birthday Email Club. I charge them to set everything up plus a monthly fee and then it pretty much runs on auto pilot.
To take it a step further I also created an app so they can have a Birthday Club on Facebook which posts happy birthday offers to their customers' walls. That way not only does the person having the birthday see it, but all of their friends also know they can get birthday deals from my client's business.
I know lots of you here have your clients using AWeber so if anyone is interested I would be happy to type up instructions on how to setup a birthday club for AWeber lists. It's not as easy as with some systems but it can be done.