[benjijay]

I have two such playlists and rarely deviate - one is a spotify playlist simply called 'Work' shared by another user with around 180 hours of mostly instrumental tracks by various artists, and the other is the soundtrack to Portal 2 (released by Valve as "Songs to Test By"), which is mostly ethereal industrial noises and a good rhythm

Typically I know which one I 'need' for a given task, and I tend to find that not needing to go hunting for a new one each time genuinely speeds me along

But of course, sometimes what I really want is to pick juuuust the right album...