Sometimes you just have to go for the easy solution. Browsing back issues of Western Interiors & Design online earlier, we came upon this page of picture ledges (jump below for close-ups), and we realized we're never going to get around to doing the hanging collage of art thing. Picture ledges are the way to go. That way we can swap out art without having to mess with a lot of holes in the wall, and we won't always be straightening frames after we brush against them or slam the door.
Images: Western Interiors & Design, August/September 2007