Stratus is a live cover version of the track by Billy Cobham, which first appeared on his 1973 album Spectrum (written by Billy Cobham).
A live version from 22 October 2010, MCH MultiArena / Jyske Bank Boxen, Herning, Denmark was streamed on Drfunkenberry.com beginning 2 November 2010 to promote the upcoming Welcome 2 America Tour.
Prince has performed the song regularly since 2007, usually in smaller venues, and often uses it to highlight solos by each band member. No studio version by Prince is believed to exist.
On 16 July 2011 a 2:33 live performance of the song from 15 Jul. 2011, Arena Santa Giuliana (Main Stage), Perugia, Italy was streamed on Andy Allo's Facebook page.
On 2 February 2013 a 4:58 live performance of the song from 16 January 2013 (show 1) Dakota Jazz Club & Restaurant, Minneapolis (MN), USA was streamed on 3rd Eye Girl YouTube channel.
On 3 April 2013 a 4:37 audio video instrumental rehearsal medley of Boom followed by Stratus (titled as BOOMSTRATUS) was streamed on Madison Dubé's Vimeo account, with revolving photographs of the 3rdEyeGirl band as background images behind the track.