I was looking for a good introduction to Emacs for some friends and stumbled upon the truly excellent Guided Tour of Emacs on gnu.org. And unsurprisingly it contained a few useful minor modes of which I had never heard.
icomplete-mode shows completions in the minibuffer as you type. If you’re too impatient to hit tab, then this is the minor mode for you.
This global minor mode solves an inconvenience that had always bothered me. Typically, to see a list of buffers without resorting to the mouse, one has to
C-x b TAB to see the list of buffers, or
C-x C-b and then toggle over to the other window (
Ctl-o) to use dired to select a buffer. Too many keystrokes.
iswitchb-mode turned on,
b shows a list of avaialble buffers in the mini buffer, narrowing them down as you type. A much easier way to jump between dozens (hundreds?) of open files.
Update: Looks like
iswitchb-mode has been replaced with the far superior
ido-mode as of Emacs 22.