The thing I want to share is this. It's actually a fairly old link. It's been floating around since Portal 2 came out. All in all the page really isn't anything special. It's a picture of Chell - the main char from Portal 2 - sitting out in a field on the companion cube and smiling up to the rain. For sound the website has the song "Exile Vilify" on repeat and another sound file that plays the sound of rain.
To me, this is honestly a "the sum is greater than the parts" thing. I don't know what it is but something about that image, the rain, and the song just makes something I can listen to for hours on end. I've done it recently while editing a story I wrote in November and while planning sessions. No matter what it keeps me on task, calm, and soothed. Maybe it will work the same for you. Oh, and for anyone who wants to see kind of a cool music video, here is one:
And once again a link to the page I'm talking about. I hope it serves you as well as it has for me.