In 2016 Australian company Flight Centre features Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch in it's "Where do you want to go?" advertisement at 0:19 - 0:24!

The actor, Taron Egerton spent most of his childhood in Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch. In 2016 Taron appeared with Hugh Jackman on Jimmy Fallon's "Tonight Show" where Jimmy and Hugh try to pronounce Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch.

In 2015 superstar Naomi Watts pronounces Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch whilst appearing on the highly rated show "Jimmy Kimmel Live" in the USA and in the process stuns the show's millions of fans, not to mention the host and his side-kick. It probably helps that Naomi lived in Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch as a child and speaks fluent Welsh.

In 2011 the manufacturers of the Isle of Anglsey version of Monopoly said fitting Llanfairpwllgwyngyllgogerychwyrndrobwll-llantysiliogogogoch on the board created one of their biggest issues to date. Llanfairpwllgwyngyllgogerychwyrndrobwll-llantysiliogogogoch was squeezed into just one "square" on the new Isle of Anglesey version of the game and occupies the King's Cross square of the traditional version of the board. The edition was inspired by the wedding of Prince William and Kate Middleton. Following their April wedding, the royal couple settled into life on Anglesey making their first home on the island where the Duke of Cambridge worked as an RAF rescue helicopter pilot based at RAF Valley.

In Sid Meier's computer game Civilization V (2010) the "Longest Name Ever" achievement award is given to players for having a city named Llanfairpwllgwyngyll in their empire.
Civilization V

In 2007 the song "Red Cave" was released as track # 11 on the album "All Hour Cymbals" by the Brooklyn based indie rock band Yeasayer. It was written by Christopher Keating, Anand Mathew Wilder and Grady Owens. The song refers to the English translation of Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch ("St Mary's Church in the hollow of the white hazel near a rapid whirlpool and the Church of St Tysilio of the red cave") with the line
"i'm at the red cave"
and the verse
"mary's house in the hollow of the
white hazel rapid whirlpool
and the church of hurricane
in the lyrics.
All Hour Cymbals

In 1995 the Welsh band Super Furry Animals named their debut E.P. Llanfairpwllgwyngyllgoger-ychwyndrobwllantysil-iogogogochynygofod (in space).
Super Furry Animals Llanfairpwllgwngyllgogerychwyndrobwllantysiliogogogochynygofod (In Space) EP

Starting in 1991 as an art-rock project Llanfair P. G. was formed in St. Petersburg, Russia. It is one of Russia's oldest cult bands which became famous for a fusion of hard rock with Celtic folk influences. This garage band refers to themselves as punk although influencess of Led Zeppelin, White Stripes and thelate Iggy Pop are evident. In 2005 the group released the album "Three Again" which contains somewhat explicit vocals.
Three Again [Explicit]

In the 1982 music video by Altered Images for the song "See Those Eyes" a sign with the town's name
Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch (sans hyphen) appears at 1'53" - 1'56".

Altered Images song "See Those Eyes"

In 1979 Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch (sans hyphen) was used as a solution in a cryptic crossword compiled by Roger Squires for The Telford and Wrekin News on the occassion of a royal visit to Ironbridge for the 200th anniversary of the first iron bridge. The crossword was subsequently submitted to the Guinness World Records as the longest word ever to appear in a published crossword. The clue was “Giggling troll follows Clancy, Larry, Billy and Peggy who howl, wrongly disturbing a place in Wales (58)”. All but the last five words of the clue form an anagram.
Crossword Puzzles Guinness World Records

Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch was used in the 1968 movie "Barbarella as the password for the headquarters of the comical revolutionary Dildano viz.
Dildano (David Hemmings): [radioing instructions to the rebel army] "And our password will be... Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch"
Barbarella (Jane Fonda): "You mean the secret password is Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch?"
Dildano: "Exactly"
Barbarella [DVD] [1968]

1n 1966 the song "The Boy From..." was composed by Mary Rodgers with lyrics by Stephen Sondheim who used the pseudonym Esteban Ria Nido. The song is a a parody on the song "The Girl from Ipanema" and features Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch in the last verse of the song
   "Tommorrow he sails.
   He's moving to Wales,
   to live in Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch^*."
   [*Pronounced: HCHLAN-VAIR-PUCH-GWIN-GICH-GWAN-GAIR-ICH-WIRN-DREW-BUCH-HCHLAN-TA-SIL-LY-AW-GAW-GAW-GAWCH]
The name is juxtaposed with a likewise similar long Spanish place name, which in this case is fictional
"Tacarembo La Tumbe Del Fuego Santa Malipas Zatatecas La Junta Del Sol Y Cruz".
The song was originally performed by Linda Lavin in a 1966 Off Broadway revue "The Mad Show".
The Mad Show (1966) The Boy From... Linda Lavin (Voice)

In the 1962 movie "The Road to Hong Kong" the quack Indian Neurologist, played by Peter Sellers, asks Chester Babcock, played by Bob Hope, to say "Llanfairpwllgwyngyllgogerychwyrndrobwyll-llantysiliogogogoch" instead of the more usual "Ahh" when doing his examinination.
The Road To Hong Kong [1962 - DVD]