Great Emacs Features

>"....These days I use keyboard macros in Emacs, but the problem there is that you have to know before you do something the first time that you will want to do it again, and tell Emacs to start recording. In vi you don't need to know that in advance.

You have just realized, "Hey, that would make a pretty cool keyboard macro". Hit Control-X Control-K, and Emacs will prompt you for a "Keyboard macro to edit". Hit Control-H L. Emacs will present you with a macro editing window filled with your last 100 input keystrokes (the "lossage"). Edit to your heart's content, and hit Control-C Control-C to save."

C-h L ...is new to me, humbling for the nos of daily hours over decades I've been emacsing.