N2O, subtitled as Nitrous Oxide in North America, is a 1998 tube shooter video game developed and published by Gremlin Interactive for the PlayStation.

On planet Neptune, forces of evil in a tubular shaped circuit known as "The Torus" are creating gigantic mutated insects with the intent to invade and destroy Earth.

Producer Peter Dalton said that "We set out to create a game where the gameplay was simple on one level but completely absorbing and addictive on another.

"[5] The soundtrack was not added until the end of development, since publisher Fox Interactive wanted to sign a high profile techno band for the game's music.

Console Classics released the game under license of Urbanscan for Microsoft Windows via Steam on 29 June 2015,[23] emulated through PCSXR.