Great suggestions here Paul, thank you! I also find LOTR is great working music, and I'd also add the three How to Train Your Dragon soundtracks are great too. Also Adam Young Scores - I love Owl City but these are completely instrumental and take you on that journey without breaking your concentration with lyrics.

Hey Paul, love the suggestions! I use Focus at Will for the same sort of reasons, but will definitely have some of these playlists saved from now on!