No store would risk confusing its customers by changing its layout daily simply to flummox Jango.

ECONOMIST: Intelligent agents

Jango also gets around the problem of merchants making their products hard to compare.

ECONOMIST: Intelligent agents: Roboshop | The

Within a minute or two, Jango produces a list of on-line stores that sell the paperback, hardcover and audiotape.

ECONOMIST: Intelligent agents

Excite says that getting this to work is its chief concern as Jango is fitted into its shopping channel.

ECONOMIST: Internet shopping: The once and future mall | The

Jango has nevertheless proved that intelligent shopping agents can work for some things.

ECONOMIST: Intelligent agents: Roboshop | The

Impressive as this is, Jango will not silence the critics of shopping agents.

ECONOMIST: Intelligent agents: Roboshop | The

At the moment, Jango is relatively good at searching and comparing prices, but most automatic buying is still beyond it.

ECONOMIST: Internet shopping

Where Jango, or its equivalents, work, comparison shopping will become so easy that it will no doubt trigger a price war, driving prices down to commodity levels.

ECONOMIST: Intelligent agents

If Jango were to record its master's buying patterns and supply them to the stores it searches, it could enjoy many of the direct-marketing advantages of a NetMarket's database.

ECONOMIST: Internet shopping