Removing the blue glow from an HTML text input when selected

How can I remove the blue glow that surrounds a selected text input box using pure CSS?

This should do it:

input:focus {
    outline:none;
}

EDIT (2015): If you are designing for a wide audience, recall that the outline is often a critical accessibility feature for users who navigate via keyboards or require more apparent visual feedback. If you remove the outline, make sure to define an alternative focus state that provides appropriate visual feedback to your users.

I prefer a nice solid reset like:

input, textarea, select, a { outline: none; }

Outline 'none' on anchor tags prevents horrible focus outlines on many Android browsers.