I have stumbled into several methods of looping in JavaScript, what I like the most is:
for(var i = 0; i < a.length; i++){ var element = a[i]; }
I know I'm late to the party, but I use reverse loops for loops that don't depend on the order.
Very similar to @Mr. Muskrat's - but simplifying the test:
var i = a.length, element = null; while (i--) { element = a[i]; }