There is a famous sample application in the Java world called "Pet Store" if you are interested you can find it here. I note that the latest iteration of the Java Pet Store is focused fairly heavily on Ajax.  There was a great alternative site created to showcase various Frameworks or Methodologies for CF called cfPetmarket.  This site contained various versions of the ColdFusion application alternative to Pet Store and I found it very useful for producing community information from load-testing different Frameworks or Methodologies.

The last couple of times I went there I notice there are no longer any cfPetmarket sample applications.  Does anyone out there know who is responsible for that site, I would be more than willing to help, as I really think that was a good resource in many ways?