I did get an idea for our hallway. I'm currently watching a bunch of antique Morris prints on eBay. They'll look great with a taupe linen mat and silver gilt frame.
Not familiar with Morris prints? Here's the rundown:
"These rare prints are actual plates from a book titled A Natural History of the Nests and Eggs of British Birds by Rev. F.O. Morris, dated 1896. The plates were produced by Benjamin Fawcett of Yorkshire, a notable Victorian printer who developed the process of color printing from wood-blocks."
This is an egg print, but I've found everything from birds, to ferns and shells.