My Hobby:
Embedding NP-Complete problems in restaurant orders
[[A menu is shown]]
Chotchkies Retaurant
Appetizers
Mixed Fruit 2.15
French Fries 2.75
Side Salad 3.35
Hot Wings 3.55
Mozzarella Sticks 4.20
Sampler Plate 5.80
[[Three people sit at a table. One man at the table is ordering from a waiter]]
Man at table: We'd like exactly $15.05 worth of appetizers, please.
Waiter: ... Exactly? Uhh ...
Man at table: Here, these papers on the knapsack problem might help you out.
Waiter: Listen, I have six other tables to get to - 
Man at table: - As fast as possible, of course. Want something on traveling salesman?
{{title text: General solutions get you a 50% tip.}}