David Letterman [1]'s final Late Show With David Letterman was Wednesday night, and loads of famous guests [2] and other late-night hosts have been saying goodbye [3]. Letterman has been on the air for an astonishing 33 years, and though you might think you know a lot about the beloved host, there are probably a few things you don't. For instance, did you know he used to be a weatherman? Or the one hosting gig he was blasted for? Here are nine things you definitely didn't know about Letterman.

His First Broadcasting Job Was For His College Radio Station

In 1966, he was a newscaster for the student-run station at Ball University in Indiana but was fired [4] for "his irreverent treatment of classical music." Classic Letterman.

He Was a Weatherman

One of his first jobs was a weatherman for an Indianapolis TV station. In true Letterman fashion, he joked in his appearances; watch this clip for some of his cracks that even made the camera guy laugh.

Regis Philbin Has More Guest Appearances Than Anyone

With over 150 separate appearances! And Reej must love Dave, considering what he puts him through, like in this vintage clip.

The Show Once Aired Without an Audience

It was Oct. 29, 2012, and the audience was sent home because of Hurricane Sandy.

His Oscar Hosting Gig Was Overwhelmingly Panned

It was the year of "Oprah, Uma, Uma, Oprah," but critics were not having any of it. Despite being blasted almost universally, Letterman was actually asked back to host but never returned for the job.

His Production Co. Produced Everybody Loves Raymond

In addition to producing his own show, Letterman's production company, Worldwide Pants, produced Everybody Loves Raymond, the film Strangers With Candy, and the Foo Fighters' HBO miniseries.

The Show Aired in Primetime — Exactly Once

On Dec. 31, 1999.

The Foo Fighters Are His Favorite Band

And "Everlong" is his favorite song. They've played several times over the years, most notably after he returned from a hiatus to have heart surgery in 2000, and on his final broadcast [5].

Letterman Is the Longest-Running Late-Night Host

This year makes 33 years; Johnny Carson is behind him with 31.