Pad numbers with leading zeros

pad.js

//for that guy on #javascript
function paddedNumber(n, places)
{
	var strn = n.toString();
	var zerosToAdd = places-strn.length;
	if(places !== undefined && zerosToAdd > 0)
		while(zerosToAdd--)
			strn = "0"+strn;
	return strn;
}