I found these old color photographs of turn-of-the-century sideshows on the Library of Congress' Flickr photostream. Makes me wish I could go back in time and gank those beautiful sideshow banners. If I found those sitting in an attic today I can't decide if I'd want to keep them -- or sell them for a few grand. I'd probably keep them.
Luckily this type of graphic art still persists -- not only does it make an excellent addition to your wall decor, but it's great inspiration for wedding invitations, event posters, websites, and whatever else you find yourself designing.
Also -- the sideshow font itself is amazing. If ever a font could scream, "three-legged!" or "spectacle!", this one does.
Step right up!