I stole this idea from my friend, who is an artist and potter, and who strung up her 2-year-old daughter's finger paintings with clothespins in front of their kitchen window. We made our own art line, using twine and paper clips, because we happened to have them on hand, for the boys' bedroom. Will and Owen love to look up at it and admire their work.
A couple times I've noticed Will gazing at one of the hanging pictures and then running to the kitchen for crayons and paper so he can sit down to work on another masterpiece. Kids, of course, get real satisfaction in displaying their work.
We may just have to put up another art line on the opposite wall.