If you enjoy museums and have time to spare on a layover at AMS, the Rijksmuseum at Schiphol is a must-see -- and it's FREE. There are several masterpieces on exhibit in the space above the gift store. I'm told the exhibits change regularly, but the paintings generally have a travel theme. The museum is located on Holland Boulevard between gates E and F.
For 4.95 euros, you'll get a cup of hot milk and a "Cafe Chocolat Hotchoc spoon" -- basically a stick with chocolate molded like a spoon on one end, and you can pick from a wide range of flavors. Stir that spoon into the milk, and voila! Definitely as advertised: "A hot chocolate unlike any other." If you want an extra kick, order the Hot Chocolate Special. For 6.95 euros, that cup comes with a shot of alcohol. TIP: There are plug-ins at most tables; great for recharging your phones, laptops, or iPads. Plus, you can buy chocolate by the weight here to snack on or give away as a gift (5 euros for 100 grams/3.53 oz).