I've been creating some replicas of medieval bindings lately, and one thing that struck me about them is how old, and yet somehow "modern" many of them are in design, with their simple, clean lines.
So I've been playing around with using other elements for the covers, including more dramatic colours, and vintage buttons from the 1940s - 1970s. I really like the mix of medieval and and modern elements--kind of a very short history of design, all in one book cover :)
Here, for example, is a little red notebook I just finished. It has a green button from my button stash that I'm guessing is 1960s vintage.