"You're My Favorite Waste of Time" is a song written and first released by American singer Marshall Crenshaw. His 1979 home demo of the song was released as the B-side of his 1982 hit "Someday, Someway" and is available on his compilations The 9 Volt Years and This Is Easy: The Best of Marshall Crenshaw.

Marshall Howard Crenshaw is an American musician, singer, songwriter, and guitarist best known for hit songs such as "Someday, Someway," a US top 40 hit in 1982, "Cynical Girl," and "Whenever You're on My Mind." He is also the co-author of one of the biggest radio hits of the 1990s, the Gin Blossoms's "Til I Hear It from You." His music has roots in classic soul music and Buddy Holly, to whom Crenshaw was often compared in the early days of his career, and whom he portrayed in the 1987 film La Bamba.