Ran across this very informative video on using top. I use top like most people, which is to say I almost never touch any of the options. I have recently started to use htop quite a bit as well, since for me it has more sensible defaults and is more useful right out of the box. This video shows how useful and powerful top really is, and has motivated me spend a bit more time actually digging into the program, its options, and documentation.
Something else I learned from this video: using
to visualize interrupt load across CPUs. Very cool.