OpenGL is pretty much the basis for how things get displayed on your computer screen. I'm really enjoying working through it. The main thing I've been focusing on is real-time percentage closer soft shadows.
Percentage closer soft shadows are pretty realistic, and I don't think they've been done correctly in real time just yet. So, I've been working through this demo at nvidia.developers.com. Pretty rough stuff and a good place to start...but I think it's going to end up not as a "plug and play" situation...which I think it what they want. Here's some more images of what I've been working
By the way, this all works in realtime. So you can spin the models and everything and the shadows move around pretty well. It only runs right now at around 10 to 14 frames per second...not really acceptable...btu some optimization might fix some of that.
You can see the main problem is the dittering around certain parts of the model, which is much more complex that they show in the demo. I think this has to do with the samples the shader takes or something like that...anyways, I think it's just going to have to be something I pursue on my own.
On a side note, if you're looking for great tuts on Open GL, look up NeHe on the internet. It's really THE place to learn the basics fast!