Sample codes

OptionsBehavior

Here is a simple Post Model.

<?php
class Post extends AppModel {
	var $hasMany = array('Comment');
	var $hasOne = array('Status');

	var $acsAs = array('Collectionable.options');

	var $defaultOption = true; // or string like 'default'
	var $options =array(
		'default' => array(
			'contain' => array(
				'Comment',
				'Status',
			),
			'limit' => 10,
		),
		'published' => array(
			'condtiions' => array('Status.published' => true),
		),
		'recent' => array(
			'order' => ('Post.updated DESC'),
		),
		'rss' => array(
			'limit' => 15,
		),
		'unlimited' => array(
			'limit' => null,
		),
		'index' => array(
			// You can do sub merging
				'options' => array(
				'published',
				'recent',
			),
		),
	);
}
?>

You can use them by like:

<?php
class PostsController extends AppController {
	function index() {
		$this->paginate = $this->Post->options('index');
		$this->set('posts', $this->paginate());
	}
	function rss() {
		$this->paginate = $this->Post->options('index', 'rss'); // multiple merging at run time;
		$this->set('posts', $this->paginate());
	}
	function all_in_one_page() {
		// you can use "options" attribute wihtin finding options
		$posts = $this->Post->find('all', array('options' => array('index', 'unlimited')));
		$this->set(compact('posts'));
	}
}

VirtualFieldsBehavior

This sample uses MatchableBehavior

<?php
class User extends AppModel {
	var $hasMany = array('Post');
	var $actsAs = array('Collectionable.VirtualFields', 'Matchable');
	var $virtualFields = array(
		'full_name' => "CONCAT(User.first_name, ' ', User.last_name)",
	);
	var $virtualFieldsCollection = array(
		'posts_count' => 'COUNT(Post.id)',
		'amount_used' => 'SUM(Post.volume)',
	);
}

You can use them by like:

<?php
class UsersController extends AppController {
	function admin_index() {
		// Hey, you may feel like using OptionsBehavior :P
		$jointo = array('Post');
		$group = 'User.id';
		$virtualFields = array('posts_count', 'amount_used'); // key of collections
		$this->paginate = compact('jointo', 'group', 'virtualFields');
		$this->set('users', $this->paginate());
	}
	function profile() {
		$virtualFields = array('full_name' => false); // disable virtualFields
		$user = $this->User->find('first', compact('virtualFields'));
		$this->set(compact('user'));
	}
}