Zen Viewer is a relatively new app (available on iTunes right now) that offers a fresh take on document filing, viewing and sharing on the iPad. It works with a host of online services, provides many options for file upload and download, and it looks great, too.
It's currently selling for US$2.99, so it's worth a look. Right now, it's a buck (US$0.99)
We can start with the way it looks. You can start by "skinning" the app with a variety of color schemes and textures. There are a good number of free selections for download within the app, and more are available for purchase. I had no trouble finding a look I liked within the available free choices. You can also configure the interface in a number of ways, with sliding panels and collapsing sections. You quickly find a layout that works well for you, and you don't have to think about it again.