Webmaster level: advanced
An easy solution for web users is to use an optimizing proxy, like Chrome's. When users opt into this service their HTTP traffic goes via Google's proxy, which optimizes their page loads and cuts bandwidth usage by 50%. While this is great for these users, it's limited to people using Chrome who turn the feature on and it can't optimize HTTPS traffic.
With Optimize for Bandwidth, the PageSpeed team is bringing this same technology to webmasters so that everyone can benefit: users of other browsers, secure sites, desktop users, and site owners who want to bring down their outbound traffic bills. Just install the PageSpeed module on your Apache or Nginx server , turn on Optimize for Bandwidth in your configuration, and PageSpeed will do the rest.
 If you're using a different web server, consider running PageSpeed on an Apache or Nginx proxy. And it's all open source, with porting efforts underway for IIS, ATS, and others.