(written from a Production point of view)
Tony Jay (2 February 1933 – 13 August 2006; age 73) was the English actor who played Campio in the Star Trek: The Next Generation fifth season episode "Cost of Living". He also provided additional voices for the video games Star Trek: Armada II and Star Trek: Elite Force II. Jay filmed his scenes for "Cost of Living" on Wednesday 5 February 1992, Thursday 6 February 1992, and Monday 10 February 1992 on Paramount Stage 8 and 9.
A former member of the Royal Shakespeare Company, Jay was known primarily as a voiceover actor on many animated television shows, films, and video games. Because of his distinctively deep, baritone voice, he was usually cast in villainous roles. He is best known as the voice of Judge Claude Frollo in Disney's The Hunchback of Notre Dame, and the virus Megabyte in the award-winning CGI-animated series ReBoot.
Tony Jay was born in London, England, and attended Pinner County Grammar School in Pinner, London. He moved to South Africa in 1966, where he worked for the South African Broadcasting Corporation radio service, Springbok Radio. He was involved with Springbok Radio for over two decades, during which time he performed, wrote, produced, and adapted many serials and plays broadcast by the station, including Taxi and The Sounds of Darkness. 
Jay returned to the United Kingdom in 1973, where he joined the Royal Shakespeare Company. While performing with the company, he also took roles in film and on television. In 1986, after successful performances of The Life and Adventures of Nicholas Nickleby in New York and Los Angeles, Jay decided to move to America, choosing to live in the Hollywood Hills area of California.  He ultimately became a naturalized citizen of the United States.
On 13 August 2006, Jay died at Cedars-Sinai Hospital in Los Angeles, California, following complications from micro-surgery to remove a non-cancerous tumor from his lungs. He was 73 years old. He is interned at Forest Lawn Memorial Park in Hollywood Hills.  Jay was survived by his wife of over two years, Marta, and his 17-year-old son, Adam. 
As an actor, Jay made his film debut while in South Africa, starring in the 1970 film Lied in My Heart. Since then, he appeared in such films as Woody Allen's Love and Death (1975), Ivan Reitman's Twins (1988, with fellow TNG guest stars Nehemiah Persoff and Cary-Hiroyuki), and the science fiction comedy My Stepmother Is an Alien (1988, with Suzie Plakson and Earl Boen). He was also a distinguished stage actor, having performed in plays based on the works of such writers as William Shakespeare and Charles Dickens. In 1987, he earned a Drama Desk Award nomination for his performance in the New York production of The Life and Times of Nicholas Nickleby.
Throughout the late 1980s and 1990s, Jay had recurring roles on various television series. He recurred as Paracelcus on the TV series Beauty and the Beast, which starred Ron Perlman, Stephen McHattie, and Armin Shimerman. Other Trek actors who appeared in the same episodes as Jay included Joey Aresco, James Avery, Joseph Campanella, Ellen Geer, Anne Haney, Jim Metzler, Jeffrey Nordling, Albie Selznick, and Dan Shor.
He then played Dougie Milford on Twin Peaks, where he worked with Mädchen Amick, Richard Beymer, Gavan O'Herlihy, Ron Taylor, and Clarence Williams III. Between 1993 and 1995, Jay appeared as Nigel St. John on Lois & Clark: The New Adventures of Superman, which starred Teri Hatcher. He also made one-time guest appearances on such series as Newhart (with Ellen Albertini Dow), Matlock (directed by Robert Scheerer, in an episode with Joel Grey), Night Court (starring John Larroquette), Picket Fences (with Paul Eiding and Ray Walston), and Providence (in an episode with Robert Pine, Heidi Swedberg, and Scott Thompson).
Perhaps his most notable voice work was the evil Judge Frollo in Disney's 1996 version of The Hunchback of Notre Dame. Also supplying voices in this film were Star Trek: Voyager guest actor Jason Alexander and fellow TNG guest actor David Ogden Stiers. Other voiceover roles Jay performed for Disney include Monsieur D'Arque in 1991's Beauty and the Beast (which also featured the voice of David Ogden Stiers) and the ruthless Shere Khan in the Jungle Book-based TaleSpin series, from 1990 through 1994. Jay again voiced Shere Khan the tiger in Disney's 2003 film, The Jungle Book 2 (in which John Rhys-Davies also supplied his voice) and in the TV series House of Mouse. (Fellow Star Trek performer Jason Marsden voiced Shere Khan as a cub in Disney's 1996-97 animated series, Jungle Cubs.)
Outside of his work in Disney productions, Jay supplied the voice of Dr. Lipschitz on Nickelodeon's Rugrats, as well as in two Rugrats films (1998's The Rugrats Movie, with Whoopi Goldberg, Iggy Pop, and Andrea Martin, and 2003's Rugrats Go Wild, with Michael Bell and Ethan Phillips). He also voiced the evil virus Megabyte in the acclaimed CGI animated series ReBoot, Dregg on Teenage Mutant Ninja Turtles, and Chairface Chippendale on the cult animated series The Tick. Other shows to which he has lent his voice include Disney's Darkwing Duck, Warner Bros. Animation's Pinky and the Brain, and Nickelodeon's Hey Arnold! Additionally, he performed a number of roles in various video games, including the Elder God from the Legacy of Kain series, the Transcendent One in Planescape: Torment, the gate of the underworld (Gate) in King's Quest VI, and the lieutenant in the first Fallout game (alongside Ron Perlman, Pamela Segall, Kenneth Mars, David Warner, and Frank Welker).
From 2001 until his death, Jay worked exclusively as a voiceover actor. He continued his collaboration with Disney, which included roles in the films Recess: School's Out (along with Diedrich Bader, Clancy Brown, Ron Glass, Clyde Kusatsu, Andrea Martin, and Paul Willson), Treasure Planet, and the aforementioned Jungle Book 2. His most recent video game work includes the voice of Magneto in X-Men Legends (opposite Patrick Stewart as Professor X), and the narrator of the widely-popular World of Warcraft. From 2004 until his death, Jay voiced the character Spiderus on the Nickelodeon children's series Miss Spider's Sunny Patch Friends. Just prior to his death, Jay had been nominated for a Daytime Emmy Award and an Annie Award for his voiceover work on this series.