"Flash Delirium" is a song released by the American psychedelic rock band MGMT on their second album Congratulations. It was the first single to be released from the album and was originally referred to as a "taster" before the band abandoned their original plan to not release any singles from Congratulations in order to solidify its existence as a singular body of work. A free digital download of the song was given away on the band's official website.