Vim fans, or folks who might be thinking about trying Vim, should take a look at Jared Carroll's Vim Text Objects: The Definitive Guide.
Carroll's guide explains how to edit with "text objects" rather than thinking of Vim as a character-by-character editor. It's been said before, but Carroll's guide is a really readable and succinct look at using Vim more efficiently. Not only that, he provides a few commands that many users probably haven't seen or used yet.
Even though I've been using Vim for the better part of 12 years, Carroll taught me a few things here. Go check it out!