You have a lot of friends, people in your family, collegues of work. Some of them you have contact in Facebook .. others no. Just register your friend's birthday and let Dobbyme remember it to you in the day. And don't worry... your data is private and Dobbyme will never send emails directly to your friends.
If today is birthday of some of your friends, dobbyme will make everything he can to remember you. Every night dobbyme send emails and tweets, if you have some friend to reminder, dobbyme you send one email to you too.