Howard Crabtree's When Pigs Fly is a musical revue in two acts conceived by Howard Crabtree and Mark Waldrop. The revue has music by Dick Gallagher and lyrics by co-conceiver, sketch writer and director Mark Waldrop. The revue opened Off-Broadway in 1996 and ran for two years, and received the Outer Critics Circle Award for Best Off-Broadway Musical and the Drama Desk Award for Best Musical Revue.