Mine gets faked so often because it's really generic (think something like "100-0001"). I actually had a call from a police department telling me that a handful of people in their town reported my number under the grounds of harassment. I had to tell them it wasn't me and that my number was faked. And they claimed that wasn't possible...

I've literally done it before! Just to mess with my brother once or twice by pretending to be his own phone number calling him, and then never again. It's totally possible and frankly easy to do!