Well, I defended my thesis today. In the end, three people came to the defense: the three professors on my committee. Since they were allowed to ask questions of me during the presentation, a 30 minute presentation very quickly became a 90 minute presentation. The upside is that it's over now, and I was asked to make only minor reveisions to the actual thesis (most of which have now been made).
Unfortunately, I'm still not done. My optics course has just assigned a final project (as well as a couple of homework assignments), and it will have a final exam. And then I will be done (with undergrad work, anyway).