Fancy completion all over Emacs, not just for buffers and files. https://github.com/DarwinAwardWinner/ido-completing-read-plus

Ryan C. Thompson f7bbe8f3b3 Avoid spurious warning when loaded before ido. 12 years ago
ChangeLog 9cab43bbdf Restore compatibility with Emacs 23 and earlier 12 years ago
README.md 95c6bc7cae Fix typo (completiion->completion) 12 years ago
ido-ubiquitous.el f7bbe8f3b3 Avoid spurious warning when loaded before ido. 12 years ago

README.md

ido-ubiquitous

Gimme some ido... everywhere!

Does what you were really hoping for when you did (setq ido-everywhere t). Replaces stock emacs completion with ido completion wherever it is possible to do so without breaking things.

Get it from http://marmalade-repo.org/packages/ido-ubiquitous