My best inspiration has always been music (especially Nine Inch Nails).
To my, and everyone's surprise, Trent Reznor (Nine Inch Nails) released a 36-track instrumental album called Ghosts I-IV (and yay, there will be more volumes to come).
"This collection of music is the result of working from a very visual perspective - dressing imagined locations and scenarios with sound and texture; a soundtrack for daydreams."~TR
Now, normal NIN albums inspire me enough, but an album that from the start was visual...


So, as soon as I heard the album all the way through, I started taking pictures around my house that very night.
I made a folder in my gallery for these shots. I will be taking many, many more, and hope to have a shot for each track ("1 Ghosts I" - "36 Ghosts IV").
The folder can be found here: [link]


If you want to hear what's inspiring these photos, visit [link] and click listen for a streaming sample, download the first 9 tracks for free, or order/download the full album. Or, you can go to ainr.com and go to music to listen to even more tracks.

EDIT:
I was asked why the images are named "inspired by (name of track)".
This is a bit more explanation about the project.
I listened to the whole album all the way through a few times. For some songs I could see specific ideas (one that apparently Rob also picked up on, flowing water for 23 and 24). For others, I could see waves of color (warm colors like red, yellow, orange for some; cool colors like blur, purple, gray for others) but no definite shape or idea/object/theme, just colors. Starting from there, I took my camera for a walk while listening to Ghosts. Each song inspired a different photo. Some songs inspired a few shots, and some photos seemed to fit with multiple songs. After the sun went down, I headed in after day one, cropped (no photomanipulation) the images, and listened to one song on repeat at a time while I went back through the finished images I took from that day, making sure each song and picture matched up. Then, I titled them, according to which song inspired them.


EDIT2: Seems I'm not the only one inspired by Ghosts. Make sure to check out drawings inspired by Ghosts I-IV here: [link]