Thats some damn smart thingy google made. I had some fun trying it out. Searched a bit.

You can play Mozart - twinkle tunes from keyboard AAGGHHG FFDDSSA GGF DDS GGFFDDS AAGGHHG FFDDSSA

Intro of One - Metallica DJDG AJAG DJDG AJAGK DJDG SJSG AJAG