Birthdayalarm.com, to me is a service which has helped me remember my friend(s) birthday(s) on behalf of mine. Although it has got many other uses like sending personalised greeting cards, flowers, gifts etc & a nice calender, but I love it for the very reason stated above. It also reminds you of many other things like birthdays, holidays & events.
One nice feature of this service is that, you provide your E-Mail ID & Password to this service, & automatically invitation(s) to all the contacts in your account will be sent.
Final Verdict – Simple & efficient.