Wired Science has a nice, succinct slideshow highlighting a selection of important scientific texts. Among them, of course, is Gray's Anatomy. Tanya Lewis writes:
Without the work of intellectual giants like Einstein, Newton and Darwin, we might still be in the dark ages. But how many scientists still read the dust-ridden texts where these luminaries first expounded their theories? Thanks to the internet, you no longer have to hunt down these yellowing tomes in a moldy library vault. Here's the story of 9 famous publications that spun the scientific world off its orbit.
If you have a few minutes, it's worth looking through.
Photo from Gray's Anatomy from Wikimedia Commons