Is there a way to broadcast multiple webcams as one image for a video podcast?

I do an audio podcast and all of the hosts are attached to a computer anyway, so I was wondering if there was a way to have all of o开发者_高级运维ur webcams on, and broadcast one image live as we do our show? Does a program/online service exist for something like this?

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For Mac users, there's a free utility called CamTwist that allows you to divvy up your video stream between several sources simultaneously - desktop sharing, webcams, images, etc.

For Windows users, I've heard that ManyCam is the closest equivalent to CamTwist. I haven't used it, but it's worth looking into.