The UsersController can have a beforeFilter, you just need to call parent::beforeFilter() in it before putting any code in to make sure that the code you have put in AppController gets called. Remember, this is OO programming, so you are overriding the parents beforeFilter function when inheriting from AppController, and therefor if you still want to run the code in the parents function that you are overriding you need to call the parents function explicitly.
After going through many MANY different rememberMe components and solutions in my CakePHP program, I finally found this one, and got it working (with needed customizations) in under an hour.
Makes me regret all the time I wasted with those other solutions.
Anyhow, I've written an article about how your RememberMe component saved my life, and a little editing for post-login functions.
If you have time, I'd love some feedback.
http://blog.japanesetesting.com/2009/09/11/cakephp-and-rememberme-autologins-for-the-soul/
Really great simple component. But from the implementation i can see that the password and user gets stored into the cookie in plain.
Doesn't that cause security issues?