Pen/Pencil and Paper for serious equations will beat any I/O interface anyday. Even tablet recognition pales in comparison, though direct tablet drawing might come a close second. I do this for all the notes I need to take, and as an added benefit, I'm forced to review my notes if I want to enter them onto my computer when I have more time. Plus, you can absorb the lessons better if you're not focused on the details of entering long equations into your computer.

Was it carried by those terrorists we let in to fly planes into those buildings? ;)

I am nearly done a double degree, B.Sc in Computer Science and a BA in Philosophy. So many people tell me that "that's an interesting combination" and roll their eyes slightly, but I think that the two are more closely linked than most other fields of study, besides some of the obvious, like Math and CS. Especially when you consider the impacts that advances in AI will bring in the next decade or two, and many other aspects as well. I haven't done much to combine the actual studies of the two, besides the obvious commonalities of logics in the two, but I'll at least be able to finish my CS degree with the ability to properly write down my ideas and convey them to other people in a clear and concise manner, and that alone is worth the Phil. degree. It's not for everyone, but I think people should look into at least a few Phil courses in any of their studies.