RAM Part RAM-VBD-128-SW1 :

This is a seriously heavy duty application.  It isn't very complicated to install either.  The weight of the mount is roughly ten pounds and it is made of metal.  And a very cool feature is that it can be expanded to hold other items like a GPS or satellite radio.

This Laptop Stand Drill System installs with minor drilling and bolting while using the existing hardware to any vertical surface. This configuration provides a telescoping feature that ranges from 12 to 18 inches. Dual swing arms provide articulation and 12 inches of reach for passenger and driver access to the mounted device. Patented rubber ball and socket joint provides additional adjustment as well as shock and vibration isolation. The RAM Tough Tray™ is spring loaded to accommodate 10 to 16 inch wide laptops (17" screens). The tray features four adjustable retaining arms with rubber grip feature. These arms can be moved both vertically and horizontally. This allows for a custom fit for varying thicknesses of laptops and the freedom of not blocking ports or drives.