Of late, it's been seventies easy/funky rock - Gerry Rafferty, Atlanta Rhythm Section, that sort of thing. This is among the many kinds of music I grew up on, but not exactly because it was anyone's "thing" particularly. It's good stuff, often really good stuff (not quite the white bread same thing, but another groove I really love - Bill Withers' Ain't No Sunshine, or just about any track of his).
Something about the buzzing funk but the soft rock goes-down-easy-ness of this music really works for me creatively. It reverts me out of the present time, almost firmly taking me out of my own head and sitting me down with a rhythm that can be dramatic, but also comes to the calling. It's easy and crunchy at once - the echoing rasp of "Driver's Seat" opening up a space for my creativity to work - or the infectious but gentle "Couldn't Get it Right" bouncing my brain along.
For the writers amongst my readers - or just for those who like to work with music propelling their time along, especially the work days - what is the soundtrack of your productivity?