A diversity of technologies is increasingly being used to draw people's attention to certain kinds of information in an attempt to change what they do or think. Pop-up ads, warning messages, reminders, prompts, personalized messages, and recommendations are some of the methods that are being deployed on computer screens. Fogg (2003) has labeled this phenomenon persuasive technology; interactive computing systems are deliberately designed to change people's attitudes and behaviors. Traditionally, media such as magazines, newspapers, pamphlets, radio, and TVhave been used to persuade people to join a good cause, give up a bad habit, donate money, or buy a product. For example, a picture of a starving child with big round eyes staring out at the reader on the front of a newspaper is commonly used by charities. The effect is to pull at the readers’ heartstrings, inducing feelings of guilt and, in so doing, spur them on to sending money.