It is the song used in the trailers to the Pineapple Express movie about drugs and violence.  Surprisingly, this song (and the movie - trailers, at least) make me want to be something epic, which considering the context of both is rather strange.

Download audio file (mia-paperplanes.mp3)

About the artist:

Mathangi "Maya" Arulpragasam (born on July 17, 1977 in Hounslow, London, England) is an acclaimed artist, film graduate and musician. She is the daughter of a Tamil revolutionary. She is best known by her stage name M.I.A. Her music style contains elements of grime, alternative, hip-hop, reggae, dance, and electronic music.

M.I.A. graduated from Central St. Martin's College of Art and Design with a degree in fine art, film and video. She has been noted for her idiosyncratic style in her music, her sense of fashion, and other artistic output.

In 2000, she did the cover artwork for the album The Menace, by Elastica and directed the music video for their single "Mad Dog God Dam." She filmed a North American tour of the band. In 2002, she published a book of art inspired by the Tamil rebellion and her childhood in Sri Lanka. She met the musician Peaches who introduced M.I.A. to the Roland MC 505. M.I.A. wrote and recorded several songs on a demo using a 505, including the song "Galang."

Information from wikipedia.