*Very* simple URL parser.

url.js

function URL(href) {
	
	var element = document.createElement('a');
		element.href = href;
	
	this.protocol = element.protocol; // "http:"
	this.hostname = element.hostname; // "example.com"
	this.port = element.port; // "3000"
	this.pathname = element.pathname; // "/pathname/"
	this.search = element.search; // "?search=test"
	this.hash = element.hash; // "#hash"
	
	this.href = href;
	this.host = element.host; // "example.com:3000"
	
	this.query = this.getQuery(); // { search: test }
	this.resulting = this.protocol + '//' + this.host + this.pathname + this.search + this.hash;
	
}

URL.prototype = new (function () {
	
	this.getQuery = function () {
		
		var queryString = this.search.substring(1), // remove ? from start
			queries = queryString.split("&"), // split by &
			parameters = {};

		for (var i = queries.length; i--;) {
			
			var query = queries[i].split('='); // spilt by =
			
			if (query[0] && query[1]) parameters[query[0]] = decodeURIComponent(query[1]);
			else if (query[0] && !query[1]) parameters[query[0]] = '';
			else if (!query[0] && query[1]) parameters[''] = query[1];
			
		}
		
		return parameters;
		
	};
	
})();

function url(href) {
	return new URL(href);
}

url.min.js

function URL(a){var b=document.createElement("a");b.href=a;this.protocol=b.protocol;this.hostname=b.hostname;this.port=b.port;this.pathname=b.pathname;this.search=b.search;this.hash=b.hash;this.href=a;this.host=b.host;this.query=this.getQuery();this.resulting=this.protocol+"//"+this.host+this.pathname+this.search+this.hash}URL.prototype=new (function(){this.getQuery=function(){var e=this.search.substring(1),a=e.split("&"),c={};for(var b=a.length;b--;){var d=a[b].split("=");if(d[0]&&d[1]){c[d[0]]=decodeURIComponent(d[1])}else{if(d[0]&&!d[1]){c[d[0]]=""}else{if(!d[0]&&d[1]){c[""]=d[1]}}}}return c}})();function url(a){return new URL(a)};

What about browser compatibility?
But nice thing!

It only uses very basic DOM and String operations so it should work everywhere.