Suddenly I have to type one character off to the right to get the intended character. Typing p gives o, typing w gets q, etc. Calibrating didn't help, rebooting didn't help.

Problem is intermittent, seems to be getting better as I type. What could cause this? I can't scroll by scrollbar because I can't touch screen far enough to the right of scrollbar!

Something like this has now happened to me three times, and then cured itself. I wonder what causes it? When it is happening I just have to learn to type a few characters to the left of the one I want to hit -- a hassle, but do-able. Then it is fixed in a day or two. It doesn't seem to be getting worse or more frequent.