Here are two other ways that will speed up your store using different methods:
Full Page Cache Magento Extension - This will reduce page generation time. If your Web site is slow because you have many concurrent users, many products, or an underpowered server, then a full page cache can quickly and easily reduce page load.
Site Optimizer - This reduces page load time by reducing “weight” of your page. This means your CSS / JS / HTML is reduced and merged and expires added to images so the browser can make more efficient requests to your store.