Interesting article about hotel bookings through Facebook

Hotel Bookings Migrate From Web Sites To Facebook & iPhones
http://inventorspot.com/articles/hotel_bookings_migrate_web_sites_facebook_iphones_42479

The Best Western Hotel President Berlin was the first Web 2.0 hotel in its region to launch an online booking widget for Facebook, the Web and soon, the iPhone. Powered by Worklight, a Web 2.0 enterprise service, the widget allows customers to check rates, promotions and book rooms at a 10 percent discount direct from its Facebook page.

Do any hostels offer discounts through Facebook or Twitter?