The images in the gallery below are all works of art that I find inspiring and demonstrations of amazing skill. For each, I've written up a short blurb about what I find interesting about it. I found all of these by digging through the online and public domain collections of some major institutions. What I like about all of them is they are not Big Deal works that you'd typically see in books or museum catalogues. Rather, they are hidden gems that I was delighted to discover.
Another reason for creating this is that I believe a big part of learning to draw well is being able to tell what is excellent drawing from what isn't. A good way to cultivate this kind of discrimination is to spend some time with excellent work by master artists. I've shared what I think is worthwhile for each of these, but it will be up to you to decide for yourself.