The season 4 episode "Head Game" only featured Frasier for the first few minutes, and the rest of the episode is entirely centered around Niles. This role should have been written for Frasier, but Kelsey Grammer wasn't available as he was being treated for his addiction problems, so it was re-written for Niles instead. This is also the reason why the plot involves Niles filling in for Frasier on his radio show, because the show is integral to the plot.

In the premiere episode of the sixth season, the show took over the time slot previously occupied by Seinfeld. The episode opens with Frasier auditioning for a TV show after being fired from his radio show, and his opening speech is a reference to the acquisition of "Seinfeld"'s slot: "Before we begin, I'd like to say how honored I am to be taking over this slot. Obviously, I have some rather big shoes to fill - my predecessor here was much beloved. But I have never been one to shrink from a challenge and I'm sure we'll enjoy many happy years here together in my new home."

Bebe Neuwirth was offered a regular role on this series as Lilith but she turned it down so she could return to the Broadway stage. She appears only as a guest star.

There is a real radio station with the call letters KACL. It's an FM station (98.7) in Mandan, North Dakota.

The above trivia can be found at
http://www.imdb.com/title/tt0106004/trivia

In the premiere episode of the sixth season, the show took over the time slot previously occupied by Seinfeld. The episode opens with Frasier auditioning for a TV show after being fired from his radio show, and his opening speech is a reference to the acquisition of "Seinfeld"'s slot: "Before we begin, I'd like to say how honored I am to be taking over this slot. Obviously, I have some rather big shoes to fill - my predecessor here was much beloved. But I have never been one to shrink from a challenge and I'm sure we'll enjoy many happy years here together in my new home."

Of all the trivia about Frasier I find this one the most ironic of all! Before I started watching Frasier, Seinfeld was my all-time favorite TV series, and I was completely floored when I read that my NEW all-time favorite TV series had taken over its' time slot! I think that is the coolest thing ever! No wonder I find myself comparing Seinfeld to Frasier a lot! In fact the first Frasier story I ever wrote was a Frasier/Seinfeld crossover! ;) And I love that the CW station shows 2 episodes of Seinfeld followed by 2 episodes of Frasier every night! An hour of pure Heaven! :angel:

And I have to say that I LOVE that 'tribute' that Frasier did to Seinfeld! That was awesome!