Tempting as it might be (and I'm sure you're joking), don't. There was a case about this and the employee whose ears were permanently damaged won the lawsuit.
We got a call from this number today, promising to "put us on the front page of Google.com." They wanted to set up a demo to show us their SEO, by the end of which we'd be on the front page. I declined.
Yes. When they call, ask if the person can hold for just a moment. Then, leave them on hold and don't go back to that line for at least 20 minutes. This really only works if you have more than one phone line, so that you can continue to conduct honest business with honest people.
Dozens of calls a week come to my cell phone from this "Beaverton, OR" number. There is nobody on the line if I pick it up. I have identified the number in my contact list as SPAM so it now shows as SPAM on my caller ID screen. I can just disconnect the call immediately. But this is still an unwelcome annoyance.