Software which seems to be smarter than the person who asks "Do you want FriesWithThat??" may someday do more than just keep half the spam from getting into your mailbox, and most of the viruses too.
One of the vehicles of DistributedArtificialIntelligence?. Agents have their own thread of control and should be capable of balanced proactive as well as reactive behaviour. Plus, an intelligent agent may have to be sociable in order to reach its goals.