Troy McClure was voiced by Phil Hartman until the actor's untimely death in 1998 and the character has been retired since then.  McClure is a washed up star from the 1970s that is the star of many infomercials, educational films and movies.  At one point, McClure married Selma in order to attempt to revive his career after rumors of a paraphilia.

Troy McClure Quotes

Troy McClure: I'm actor Troy McClure. You may remember me
from such TV series as: Buck Henderson: Union Buster and Troy & Company's Summertime Smile Factory.

(Troy McClure hosts an infomercial for a new type of candy that cleans and straightens teeth.)
Troy McClure: Ladies and gentlemen, I'd like you to meet the inventor, Dr. Nick Riviera.
(Audience applauds)
Dr Nick: Thank you, Troy! Hi, everybody!
Audience: Hi, Dr. Nick!

The Simpsons Quotes

Sir, I got carsick in your office.

Ralph

Mr. Burns: (reading Homer's letter) "Dear Mr. Burns. I'm so glad you enjoyed my son's blood, and your card was just great." Why Simpson, you've made my day, you're a true gentlemen.
Homer: Well I-
Mr. Burns: Hello, there's more. (continues reading) "In case you can't tell, I'm being sarcastic. You stink! You are a senile bucktoothed old mummy with bony girl arms and you smell like an elephant's butt!"