Not that long ago I gave a ThoughtWorks geek night presentation on Post-Redirect-Get and how to mess with the Spring Framework to make it happen. I've put up the presentation and the code that I used for it on GitHub. Feedback is always welcome....
For a while now I've been flying the flag for using a post-redirect-get design pattern when writing web applications. In my opinion the current crop of web frameworks still make it very easy to do the "bad" thing since to do PRG properly you need to think what kind of an interaction you want with users and not cop out saying its technically very difficult in . If you resort to ActiveX controls, popups without navigation bars and/or weird javascript hacks to stop users from clicking refresh or back buttons then perhaps you should have written a better web application....
I've uploaded to GitHub (http://github.com/tomcz/pico-webapp/tree/master) the web application that I use to teach people about dependency injection (using PicoContainer), post-redirect-get browser interaction, RESTful URIs and strict template rendering (using StringTemplate). This application does not use Spring Framework by deliberate design - as soon as I introduce it to any teaching session I spend more time talking about Spring then talking about what I am usually there to accomplish. As usual, any comments, bugs or enhancement requests are very welcome....