I'm often preferring silence these days, but when I do feel like tunes, I like stuff that's doesn't tear my attention away from what I'm doing.

The Aphex Twin:

  Analogue Bubble Bath
  Analogue Bubble Bath 2
  Analogue Bubble Bath 3
  Analogue Bubble Bath 3.1
  Analogue Bubble Bath 4
  Analogue Bubble Bath 5
  Selected Ambient Works

Also, Trace Nico and Speedy J.