The Laptop Shade. €25.00 buys you some screen legibility even in the brightest sunshine. Shame it looks like something out of Attack of the Killer Tomatoes, though. 

 A left hand and right hand panel assembly, each consisting of an integral side panel plus top panel, are hinged to a mounting strip. The mounting strip becomes attached to the outside of your laptop’s lid using factory-pre-positioned pressure-sensitive hook & loop strips. The assemblies overlap near the top center to form a 3-sided tunnel around the screen, approximately 9 inches deep. The resulting tunnel blocks most light infiltrating around the top and sides of your screen.