Thule's rooftop boxes significantly increase the carrying capacity of any vehicle. They include quick-mount Thule hardware and fit on Thule crossbars (sold separately), and most after-market and factory-installed racks. They're also aerodynamic to minimize drag and boost your mileage. And they're made of impact- and scratch-resistant ABS plastic for the ultimate in durability. Thule's Frontier model boasts 11 cubic feet of capacity (enough to carry 6 pairs of skis) and a central locking system.
If you drive a van or SUV for its carrying capacity, but find the expenses of driving it a bit excessive, you might be interested to learn that you could instead drive a sportier and smaller car with a rooftop box. In most cases this setup exceeds the carrying capacity of your SUV and gets significantly improved mileage, too. Plus, rooftop boxes provide easy access, easily fit on all vehicles and can be quickly removed when they're not needed.