My first name is relatively common; it was in the top 10 in my birth year, and has been common for most of the 70s and 80s. With this, an estimator shows 341 people with the same name as me in the U.S. 
Despite there being only about 340 people with the same name as me, I've run across several. My first job as an intern in Columbus, there was another person (Matthew S Fleming); I got several voicemails intended for him since I was in the company address book first. There was another Matthew Fleming at IBM who lived in Florida; I got at least one email intended for him.
Today, I see an email on the kexec-tools mailing list, which I just signed up for a month or so ago, since I'm working on it for my current employer. And today I see an email to the list, also addressed to matt.fleming AT intel.com.
There's about 340 other Matthew Flemings in the country, and I've worked with or near three of them (maybe more; my memory isn't great). That's 1% of the people in the country who share my name.