There are lots of talking toys out there, and some also have microphones built in, so they can respond to your voice. One such toy is "Talking Carl," an iPhone app that mimics what you say. But what happens when Carl talks to another Carl? Friggin' pandemonium.
But wait, there's more. Remember the Furby? Well, I had a coworker who made a Halloween costume out of a bunch of Furbys (yes, that's the proper plural) and left it in the front hallway of the office. The Furbys were activated by noise, so anyone who walked in would set them off. They wouldn't quiet down for ten minutes or so, idly blabbing at each other. Here's a mild example of a "Furby conversation" between Furbys "Tolu-Ka" and "Mee-Mee." The creator notes: "Sadly conversations between these two always result in one or both of them falling asleep." I can tell you from experience that after a few more minutes, your brain starts to melt, so this is a merciful feature.
WALL"¢E and EVE
And wouldn't you know it, the WALL"¢E and EVE toys can carry on a form of conversation:
Toy Story Toys
So a dinosaur, a potato, and a space ranger walk into a bar....
Here's a collection of Pokemon talking toys, triggered by a whistle.
Talking Cabbage Patch Kids
And this is just creepy. Did you know there were talking Cabbage Patch Kids? Their dead eyes and constant discussion of secrets freaks me out.
Got any more? Post them in the comments.
(Dueling Carls via Kottke.org.)