Metanoia is a compilation album by British progressive rock band Porcupine Tree, first released on 10" double-vinyl on 7 December 1998, in a limited run of 1,000 copies.

The track "Mesmer I" became the basis for tour-only piece "Cryogenics," originally intended for Coma Divine but left out during mixing.

A live recording of "Cryogenics" was later restored and released on 2020's EP Coma: Coda (Rome 1997) which made available through the official Porcupine Tree Bandcamp page.

In a critical review on expose.org, the album has been described as "in every way the antithesis of Stupid Dream, and simultaneously every bit as brilliant".

A special recognition is given to Chris Maitland and Colin Edwin who show "a masterful display of finesse and energy".