ThinkGeek (http://www.thinkgeek.com/) says will release an accessory for the iPhone 4S that works with Siri, named Iris 9000. The Iris 9000 is a voice control module for iPhone 4S & Siri that allows for you to control Siri from across the room.
Siri on iPhone 4S lets you use your voice to send messages, schedule meetings, place phone calls, and more. Apple says that you can ask Siri to do things just by talking the way you talk. I haven’t tried it, but Apple says Siri understands what you say, knows what you mean, and even talks back. What differentiates Siri from competing technologies is its ability to not only recognize words spoken in a normal tone of voice, but its capacity to pick up on the contextual meaning of a phrase, according to Apple.
To use Siri with the Iris 9000, place your iPhone into the Iris 9000 cradle and use the included micro remote to trigger Siri from up to 50 feet away. Tap the Iris 9000 remote button once, listen for the Siri chime and speak your command or question. The built in mic on the Iris 9000 picks up your voice from across the room and the embedded speaker amplifies Siri’s spoken response
You can also make and receive calls using the Iris 900 like a standard speakerphone. But you’ll have to wait a while; the ThinkGeek device isn’t due until next spring and will cost approximately US$59.99.