Cloud Nine (play), a play by Caryl Churchill

Cloud 9, a brand name for Ephedra

"on cloud (number) nine", a phrase meaning happy, euphoric, or 'high'

"Cloud Nine", a song by Evanescence on the album The Open Door

Cloud Nine (Temptations album), a 1969 album by The Temptations that also contains the song "Cloud Nine"

"Cloud Nine" (song), a Grammy-winning 1960 song by The Temptations

Cloud Nine (George Harrison album), a 1987 album by George Harrison

Cloud 9 (Battlestar Galactica), a luxury liner on the television show Battlestar Galactica

Cloud Nine (Kottonmouth Kings album), a 2007 album by the Kottonmouth Kings

Cloud 9 (comics), a Marvel Comics superhero that debuted in Avengers: The Initiative

"Cloud Number Nine", a song by Bryan Adams

"Cloud Nine", a song by Leigh Nash on her 2001 album Blue On Blue

"Cloud 9", a song by Puddle of Mudd from their album Life on Display

"Cloud Nine", a song by John Legend on the album Get Lifted

Cloud9, a mobile phone company in the Isle of Man

Cloud nine (Tensegrity sphere), a name for giant sky-floating Tensegrity spheres, named by Buckminster Fuller

"Falling From Cloud 9", a song by Lift To Experience on their album The Texas-Jerusalem Crossroads

CloudNine Communications, an ISP in Great Britain from 1996 to 2002