brent not sure how to replace default stuff like Thunar
The file manager in that picture is Dolphin -- the best one I've ever seen. It's a good replacement for Thunar, which was a big disappointment to me. Dolphin not only looks attractive, but it has no problem displaying the shares from my NAS (using the native nfs protocol), but also has no problem accessing their contents as if they were local files.
Looking through the various menus, I found Nitrogen, which is where this backgroun came from. Bunsen Lab seems to have a liking for naming things after elements, so it pays to look at menu elements themselves, instead of just their names.
And sometimes you'll need to look several layers deep. This is where I found Nitrogen. Exploring these menus is a lot of fun. It's a bit like a treasure hunt, especially when things aren't always named what you might have expected.