/*
 * Title Caps
 * 
 * Ported to JavaScript By John Resig - http://ejohn.org/ - 21 May 2008
 * Original by John Gruber - http://daringfireball.net/ - 10 May 2008
 * License: http://www.opensource.org/licenses/mit-license.php
 */

(function(){
	var small = "(a|an|and|as|at|but|by|en|for|if|in|of|on|or|the|to|v[.]?|via|vs[.]?)";
	var punct = "([!\"#$%&'()*+,./:;<=>?@[\\\\\\]^_`{|}~-]*)";
  
	this.titleCaps = function(title){
		var parts = title.split(/([:.;?!] |(?: |^)["Ã’])/);
  	
		for ( var i = 0; i < parts.length; i++ ) {
			parts[i] = parts[i]
			.replace(/\b([A-Za-z][a-z.'Õ]*)\b/g, function(all){
				return /[A-Za-z]\.[A-Za-z]/.test(all) ? all : upper(all);
			})
			.replace(RegExp("\\b" + small + "\\b", "ig"), lower)
			.replace(RegExp("^" + punct + small + "\\b", "ig"), function(all, punct, word){
				return punct + upper(word);
			})
			.replace(RegExp("\\b" + small + punct + "$", "ig"), upper);
		}
		
		return parts.join("").replace(/ V(s?)\. /ig, " v$1. ")
			.replace(/(['Õ])S\b/ig, "$1s")
			.replace(/\b(AT&T|Q&A)\b/ig, function(all){
				return all.toUpperCase();
			});
	};
    
	function lower(word){
		return word.toLowerCase();
	}
    
	function upper(word){
	  return word.substr(0,1).toUpperCase() + word.substr(1);
	}
})();

http://ejohn.org/files/titleCaps.js

I haven't take a very good look to the code, but I put it here for future reference.

Nice Caps Titles

JavaScript