01/04/2012 10:02 am ET

Will Arnett, David Letterman Tweet At Jimmy Fallon (VIDEO)

Ever since David Letterman figured out what Twitter was, his use of the social networking site on-air has become a thing of comedy. Who else starts almost every tweet with "@#Hash Tag"?

On Tuesday night's "Late Show," Will Arnett casually mentioned during his interview with Letterman that he thinks he has a giant head. Like a good tweeter, Letterman saw this as an opportunity to "get it out there" and fired up his "Twitter machine" (or laptop) and allowed Arnett to break the news himself.

Now, is this bit really just a couple of funny guys sending a pretty boring tweet that's directed at Jimmy Fallon for some reason? Yes. But watching Arnett politely pretend to be completely on Letterman's level technology-wise is what makes it worth watching.