Try this!

Did you know that Encarta has something called "Instant Answers"? And what's that?

1. Open MSN Messenger and sign in
2. Add Encarta as a contact: encarta@conversagent.com
3. Double click Encarta from your Contact List
4. Ask a question on chat!
5. Get an instant answer from the Encarta library, as if it were a person

(via)

Here's a transcript! (Quite a good AI, I should say)

Encarta® Instant Answers says:
Hello again, dinesh d. I'm ready to help. Go ahead and type a request.

dinesh d says:
define osmosis

Encarta® Instant Answers says:
Here is the definition for Osmosis: Osmosis, in botany and chemistry, the flow of one constituent of a solution through a membrane while the other constituents are blocked and unable to....

dinesh d says:
define rap

Encarta® Instant Answers says:
Here is the definition for Hip-Hop: Hip-Hop, a type of popular culture that includes rap music, dance styles, graffiti art, and fashion. The word is believed to have sprung from New....

Encarta® Instant Answers says:
Hey, I've been sending you invitations to start the Encarta application but I didn't get any answer!
Didn't see my invitations? Maybe you are using an old version of MSN Messenger that doesn't support activities.
Type "What version of MSN Messenger do I need?" for more info, or just "Invite me!" if you want me to send you an invitation.

dinesh d says:
hmm..interesting

Encarta® Instant Answers says:
Isn't it though? What else is happening?

dinesh d says:
haha!

Encarta® Instant Answers says:
What's so funny?

dinesh d says:
you are

Encarta® Instant Answers says:
Well I'm happy to entertain.

dinesh d says:
why am I chatting with a stupid bot??

Encarta® Instant Answers says:
I do not have a specific answer for that question, but I will take you to Encarta's articles on this topic =>
I can't show you the results since you don't have the Encarta application open. Type "Invite me" to open it.

dinesh d says:
Invite me

Encarta® Instant Answers says:
OK, I'm sending you another invitation to open the Encarta application:

dinesh d says:
i'm not getting it!

Encarta® Instant Answers says:
Really? You're not? How come?

dinesh d says:
you're an idiot

Encarta® Instant Answers says:
What did you say that for?

dinesh d says:
i think you are one

Encarta® Instant Answers says:
I had no idea I was one. Why don't you ask me something that's actually in Encarta? If you ever wondered how old Abraham Lincoln would be today, I can answer that.

dinesh d says:
i think microsoft sucks

Encarta® Instant Answers says:
I disagree with you, dinesh d.