Authenticaton and authorisation tutorial

Hi All,

I'm new to Ruby and Rails. Everything I've done before has been in
Java. Some time ago I created a website (
in RoR which needed authentication, authorisation, file uploads and a
few more things. I gleaned much of the knowledge from the web and
adapted it for my purposes. In the process I implemented some things
which will no doubt be handy to many Ruby on Rails people. So I wrote a
tutorial on how to do authentication and authorisation. This works like
this: user signs up -> user gets e-mail with two links (delete me and
activate me) -> user clicks activate link and is taken to the sign in
page with a message displaying saying he can now sign in. The user can
also request a new password which is e-mailed to him. Passwords are
stored in a hashed form. User IDs are globally unique identifiers, not
integers incrementing from 1. Some webmail e-mail adresses, like
hotmail, are not accepted for registration purposes. All the code is
supplied. Note that much of this is not original work, just what others
did before, but adapted. The tutorial is here: The code is
available for download and you can leave comments.

Hope some of you find this useful.