I'm pretty much in love with Flipboard since it means I can view some of my favorite sites in a more image-focused (and, perhaps, brain-focused) way. I tend to get super distracted away from websites and blogs when it's full of links, or when I have a manga tab open, which makes viewing via the Flipboard app that much better.
One of my favorite sites to view with Flipboard is My Modern Metropolis. It always has stunning art and there are so many artists that I wouldn't have otherwise been made aware of without the site. The image above is just one example. I get lost in the shading and subtle textures.