I wanted to check one of my answers in my Linear Algebra course, so I broke out the HP-15C that was issued to me at West Point in 1983, broke out the user's manual (which I probably hadn't read since 1984 or 85), and did a little matrix reading. Checked one of my answers--turned out to be correct--now I have one short blog post to go and then I'm off to bed.
I also have the HP-15C app installed on my iPhone (which I don't use as a phone, but that's another story). It's a great calculator. Who has two thumbs and loves RPN? This guy!
P.S. Still haven't received word on how I did on the test I took last Friday. I'll admit to being a lot more confident going into it than I was coming out of it.