My friend Nick is good at answering the questions I didn’t even know I wanted to ask. For example, how many electrons per song on an iPod?

At approximately 4 minutes per song (Apple’s average), we can play through 150 songs in 10 hours (far less than the 1000 song storage capacity), giving us approximately 1.09�1020 electrons used per song.

That’s downright efficient compared to the piggish 160 gig iPod Classic, which weighs in at 850mA�h, 40h: 1.27�1021 e / song.