Help with DRY. I feel like im doing more then I have to.

Throughout my Message controller, I do this a lot:

@message = Message.find(params[:id],:conditions => ["user_id = ?",

Since you need to authenticate to use this app, is there a way i can
tie the Accounts model in with the Message model so I dont have to pass
in the user_id everytime?

Do you have a helper method that provides the current user? Something like:

def current_user
  @cur_user ||= User.find(session[:user_id])

Then set up a relationship in your user model:
class User < AR::Base
  has_many :messages

then you can do

If you go through the messages relation, it constricts it only to
those messages that have the user_id belonging to that user.

Alternatively you could do
Message.find_by_id_and_user_id(params[:id], session[:user_id])

or set up a method in your Message class.

I think setting up the has_many :messages association and going
through that would be the most idiomatic way.

Also use the accessor method session instead of the instance variable
@session, which is deprecated.