Before you put a cybertwin online, be sure to read the company's privacy policy. The MyCyberTwin site and the embedded cybertwin interfaces don't yet contain any advertising, but RelevanceNow does reserve the right to give voluntarily provided personal information to advertisers. This could become a significant revenue source for the company, given that advertisers often pay extra to reach "qualified leads" who have provided demographic data or professed an interest in a specific product area.

Also, be careful what you tell another cybertwin. Although the MyCyberTwin site does not make it obvious, the service actually saves a transcript of every chat session for the perusal of the cybertwin's owner. That's mainly so that visitors can leave information such as phone numbers, e-mail addresses, and requests for more information. But an unsuspecting user who gets into a racy conversation with a cybertwin on the assumption that there's no one at home might be in for some embarrassment.

MyCyberTwin can be a bit slow, taking up to 10 seconds to "think" before it responds to a visitor's question. Nonetheless, creating a MyCyberTwin chatterbot can give your online admirers much deeper, quicker access to your personality and background than dry autobiographical statements or even months of blog entries.

"People are spending a lot of time putting their personalities online," Capper notes, whether through their MySpace pages, blogs, or avatars in virtual worlds such as Second Life. "It may only be for an audience of 10 people, but it's important to them, and it's a taste of things to come. This way, you can have your friends chat to you when you're sleeping. It's about engaging with people and answering their questions without having to go through a hundred e-mails."