I just ran the hose down the back, suction cupped it a few times and put a plant in front of it. You can't see it unless you look through the side of the tank. I also used a flexable airstone and buried it right below the surface of the gravel. Makes a nice cascade effect.
Thanks gunnie for those great links! One of my pet peeves. All those hoses, filters, heaters that show at the back of my tank. I think I could really enjoy a remake to dress things up a bit. Do you have any idea if "cork bark" and a local cottonwood would be similar? The bark looks the same. I suppose boiling it to remove the tannon would always be advisable. I also love the moss wall idea. What moss would you suggest? Should help with nitrate.