I just tried to call an old childhood friend to wish him happy birthday. We haven't been in touch for around 20 years but somewhere I heard the state he lives in. Searching for his name on Google is not real fruitful, because for some odd reason there aren't many people with his name or the precise spelling of it.
I came up with one hit from that state. I called the number and got an answering machine, with a voice that said his name but didn't sound like his voice. So I hung up. But since that was the only choice, I rethought it and called back and wished him a happy birthday anyway, saying if he was so and so from the place we grew up.
I just happen to remember people's birthdays 40 or 50 years later. So I think of them at least once a year. I have another friend in a foreign country, and we're also out of touch for many years, but I remember his birthday every year.