3 lines of code, that make writing pure JS so much quicker. Borrowed mostly from http://jsfiddle.net/leaverou/hRz8K/embedded/result,js/

js-selecting-that-doesnt-suck.js

function $(id) { return document.getElementById(id); }
function $c(class) { return document.getElementsByClassName(class); }
function $t(tag, container) { return (container || document).getElementsByTagName(tag); }
function $$(expr, container) { return (container || document).querySelectorAll(expr); }