I started my first programming job back in 2000 and was reading Cryptonomicon at the time and came across this little gem in the book:

"When Randy gets back to his cell, he sits crosslegged on his bed with the Walkman and begins dealing out the CDs like cards in a solitaire game. The selection is pretty reasonable: a two-disc set of the Brandenburg Concertos, a collection of Bach organ fugues (nerds have a thing about Bach)"

So I thought 'why not' and got a two-disc set of Bach's Brandenburg Concertos. And sixteen years later I still listen to it when I'm working and have never tired of it. Great music for focus.