You know how places like the Penney's portrait studio give you all those free 8x10s? This is our answer for what to do with them. We bought some really cheap frames and stuck the pictures in them, and then we space them very uniformly on the wall in the bedroom and the living room and the hallway (no pics of the hallway, though). This allows us room to expand, but it also looks nice in progress. Of course, we may eventually run out of wallspace, but until then, this works for me!
You can find more ideas for Works for Me Wednesday at Rocks in my Dryer.