include() - load scripts asynchronously w/375 bytes of code - e.g. `include(src, cb)`

include.js

function include(url,success) {
	var head = document.getElementsByTagName("head")[0], done = false;
	var script = document.createElement("script");
	script.src = url;
	// Attach handlers for all browsers
	script.onload = script.onreadystatechange = function(){
		if (!done && (!this.readyState || this.readyState === "loaded" || this.readyState === "complete") ) {
			done = true;
			if (typeof success === 'function') success();
		}
	};
	head.appendChild(script);
}

// usage:
include('http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js',function(){
	alert('jQuery loaded. yay life') 
});