Required CheckBox validation in ASP.Net MVC 2 onwards

Having forms with checkboxes that require users to check them to be valid is a pretty common phenomenon on the internet today, however when thinking about this in terms of ASP.Net MVC it can not always be obvious what the best approach to take is. Thankfully the ASP.Net MVC team gave us the support to create a really simple solution when they added inheritable validation classes to the framework.