I was just wondering the same thing and the Search came up with this thread. This month and last in Sport Aviation there are articles describing 3D printing of fairings and such.
My wife has been teaching Engineering classes at the local High School and they have a couple of nice 3D printers. We have had one at our house over the summer and have played around with it a little bit. I'd like to try some aviation related objects to print, but haven't come up with anything yet.
Maybe some sort of defroster venting on the top of the panel might be something to try. Other easy items might be something like the little flap shaped handle for switches, knobs, grips, trim wedge, a junk tray that would fit between seats, etc. How about a miniature RV model?
Anyone have any other ideas?
MakerPlane.org mentions some 3D printer file downloads, but it seems to be offline.