Static resources on Force.com

One of the interesting things I ran into today while making customer portal pages look like another external web-site using static resources

•  use timestamp in the resource url
• For example if you are using static resources in a zip file (one of the best practices for maintaining static resources) use timestamp in the URL  /resources/id/timestamp/<filepath>

If you don't use this method to access, you may see a delay in the resources getting reflected by Salesforce Content Delivery network.

The other idea may be to use Amazon CDN which would make the page load quicker