I love pulp fiction book titles and vintage paperback book covers, and I just found on a website that, because of my own personal taste, I assume everyone will enjoy: http://www.bookscans.com. The navigation is a bit difficult, but there are over 30,000 paperback covers (as well as a huge collection of colophons, also known as printers marks, which is what I was looking for in the first place).
It's a treasure trove of American classics like Love Me Sailor and Someday I'm Going to Kill You. Please check it out and post comments with your favorite book covers or titles or both. Imagine you're in an old bookstore in New Orleans twenty years ago and need a flashlight to go through a box you found in a corner--I remember that bookstore well, but that's another story.
Follow the link above, poke around his collection, and when you see one you like, click on the image to enlarge it, right click and select copy, then paste into your comment below. Or just tell us about it. I have to go now, and finish reading...