U, U, D, D, L, R, L, R, A, B, Select, Start Lyrics

Lyric discussion by Pandorus 

Cover art for U, U, D, D, L, R, L, R, A, B, Select, Start lyrics by Deftones

It's called the Konami Code, it's famous because it was first used in Gradius and one of it's most famous uses is in Contra.