http://www.ayende.com/Blog/archive/7842.aspx
I tried to get an overview of all the posts I wrote so far about Castle Demo App, and I got a little lost, and I guess that this isn't only my problem, so I put up a list of all the posts in the subject. I must say that I was very surprised to see that I posted so much about this (and I can think of several more topics that I want to post about).

So, without much further ado, here is the list as of right now:

1. Building a full blown application with Castle
2. Castle Demo App: Getting Started With Active Record
3. Castle Demo App: Active Record Relations
4. Castle Demo App: Play with where clauses
5. Castle Demo App: Playing with the code
6. Castle Demo App: Lazy Loading and Scopes
7. Castle Demo App: Many To Many Relations
8. Castle Demo App: The First MonoRail Page
9. Castle Demo App: MonoRail At A Glance
10. Castle Demo App: Getting serious, the first real page
11. Castle Demo App: Updating our Users
12. Castle Demo App: Let There Be A New User
13. Castle Demo App: CRUD Operations on Projects
14. Castle Demo App: Complex Interactions
15. Castle Demo App: Queries and Foreign Keys
16. Castle Demo App: ViewComponents, Security, Filters and Friends

Enjoy.