Favorite emacs minor mode ?

Question

I just discovered tabbar, a minor mode that provides firefox like tabs in emacs.
I also modify org-mode into a minor mode and use it with other major modes for code folding and organizing my code, for example: (ahk-org-mode )
What are your favorite minor modes.

Are there major modes that you have turned into minor modes so you can use them with other major modes ?

Answer 1

I like auto-complete (for code completion): http://cx4a.org/software/auto-complete/

Answer 2

• autopair - autopairing of some characters ala TextMate, modern IDEs

• paredit - ultimate sexp editing mode, one cannot do serious Lisp programming without it

• flyspell and cousing flyspell-prog-mode - great on the fly spellchecking

• eldoc - on the fly hints about function parameters, etc in several languages like Emacs Lisp, Perl...

• yasnippet - template expansion framework ala TextMate bundles

• auto-revert-mode - reverts buffers, if underlying files have been changed externally

• hl-line - highlights the current line

• windmove - easier navigation between many open windows in Emacs

• show-paren-mode - highlight matching parenthesis, making it easier to spot errors with their pairing

All those minor modes are simply Godsend! I cannot live without them and they make my whole editing experience that much more enjoyable and productive...

Btw you can see much of the customizations and modes that I use in my configuration publicly available here(most of the minor mode stuff is in misc-config.el). I also recommend to everyone to follow the excellent blog Emacs Fu, when I've picked many interesting modes over the past couple of years.

Answer 3

• Icicles mostly for command completion.
• Flymake for simple syntax checks.

Answer 4

Parentheses matching, my favorite of which is mic-paren.