Starting 12 December 2010 you can travel from The Hague to the Rotterdam The Hague Airport on RandstadRail E and the new Airport Shuttle (Bus 50).
From The Hague's Central Station take RandstadRail E to the Meijersplein stop. Transfer there to the new Airport Shuttle (Bus 50). The bus rides directly to the airport.
The new shuttle rides every 15 or 30 minutes and provides a good connection for the metro and RandstadRail as well as the flight schedule at the airport. At night Bus 12 departs from Rotterdam's Central Station to the airport.