Keyboard Only Control When Hotkeys, Hinting, and Tabbing Fail I'd like to never need to reach for a mouse or trackpad.

Right now I spend most of the day mouse free. Alas, I occasionally must reach for a mouse or trackpad. It can really derail a good day.

What is the most efficient method of last resort for "clicking" those elements that have no hotkey, that I can't get any program to provide a keyboard hint for, and that can't be tabbed to?

My expectation is that the answers will be methods to move the mouse cursor and click via keyboard (like mousekeys) but any solution is applicable if it allows a keyboard to do anything a mouse can do.

Update Here's a very specific example of something that I don't know how to control by keyboard. In Firefox I'm unable to start this video:
http://vimcasts.org/episodes/comparing-buffers-with-vimdiff/

This specific example isn't too important, the point is that even with tools like Shortcat and Vimperator, sometimes hinting isn't provided. Video controls are a good example of something challenging. (Vimperator sometimes works for video controls, sometimes doesn't.) Maybe there's a better way to get hints for these?
I've settled on an ultimate method of final last resort when mousing is simply not an option. Karabiner (recently renamed from KeyRemap4MacBook) offers a "Mouse Keys Mode" which allows vim-style hjkl control of the mouse pointer and uio for left-middle-right click. There are a few options for the hotkeys that will activate this mode. My current preference is Cmd + S + D.

https://pqrs.org/osx/karabiner/

As much as possible this method should be avoided but if you, like me, often don't have a mouse or trackpad readily available then it can be useful.