shave-example.js

var post = {
  title: "Shave : Ultra simple Javascript templates",
  author: "Armando Sosa",
  category: "self-importance",
  permalink: "http://startupinmexico.com/?p=8"
}

var template = "<li><a href='{{permalink}}'>{{title}}</a> by {{author}} on {{category}}</li>";

var html = shave(template, post);

shave.js

// really simple template engine for {{mustache}} style templates. 
shave = function(str,obj){

	var rex = /\{\{[^\s]+\}\}/g;
	var matches = str.match(rex);
	
	for (var i = matches.length - 1; i >= 0; i--){
		var key = matches[i].replace(/\{\{|\}\}/g,'');
		if (typeof(obj[key]) !== "undefined") {
			str = str.replace(matches[i],obj[key]);
		};
	};

	return str;
}