Given my love for the pillows mentioned in this post its no surprise I'm drawn to this artwork:

photo of Kevin Sharkey's apartment via Martha Stewart
It's a similar idea; tonal concentric squares. What I love is that the color combos are endless and it's an easy DIY paint or Photoshop project. Great way to inject color into a space!
BTW you can find pillows similar to the ones in the above mentioned post over at Jonathan Adler:



The cool thing? The colors are customizable!