It goes la de da de da, la de da de da… Can’t remember? Just hum or sing at your monitor and Midomi will tell you. Seems to work ok.
midomi.com makes it fun and easy to find and discover music and people. For the first time, you can use your voice to instantly connect to your favorite music, and to a community of people that share your musical interests. Listen to voices, see pictures, rate singers, send messages, buy music, and more. [Source]