cVim (GitHub: 1995eaton / chromium-vim, License: MIT) by Jake Eaton is a Chrome extension that makes Chrome behave like Vim. There are other Vim for Chrome extensions, but I found this one really easy to learn. It's possibly more idiomatic than the others that I've tried.
:o has a cool history search open prompt, which supports
! (new tab) and
* (pin tab). Pressing
f shows quick open link hints that are alphabetical rather than numerical. Like Vim,
F is different to
f -- in cVim it causes links to open in a new window.
There are lots of movement commands: naturally
hjkl works, but there are some nice additions like
d for half-page down and
e for up.
I really want to see what this plugin does on a Chrome OS machine because some of them have better keyboards than trackpads, so it seems like the kind of place where you'd really want to avoid the mouse at all costs!