Michael Jouravlev at TheServerSide.com - Redirect After Post:
" PRG pattern can be rephrased like this:
Never show pages in response to POST Always load pages using GET Navigate from POST to GET using REDIRECT
Repeat these lines before going to bed.
[...] Web applications should be resource-centric. They can attain greater presentation flexibility instead of fixating on delivering a particular page. Browser should request from a server a resource, a business entity, not a page. Depending on resource availability and state server would generate different presentation for that resource. It can be a regular "read-only" web page, or a form with input controls, or a message that resource is not available or it was permanently removed. Think in terms of resources, not pages."