As a demonstration of so-called fake webcam with CamCamX, here's what we did:

• Copied PhotoBooth.app (temporarily) from a MacBook to a 12" PowerBook
• Disconnected the external iSight from the 12" PowerBook
• Opened CamCamX and dropped a music video onto Source A (could just as well have been a still image taken with a cellphone).
• Launched PhotoBooth and took a picture of the prerecorded video.
• As you can see from the screen grab, PhotoBooth believes the 12" MacBook has a built-in iSight, even though the Mac has no physical camera at all - that's how good our iSight emulation is.

Having a fake webcam is useful for uploading pre-edited video content to sites that only accept webcam input. Also, webcam performers might like to stage additional performances by repeat broadcasting earlier performances or rebroadcasting performances for viewers in different timezones. It's a handy feature, and if you were using Windows instead of a Mac, you'd pay $20 for a very rudimentary application that can barely emulate a webcam, let alone a full video mixer with multiple camera inputs.

If you need fake microphone to go with fake webcam, we suggest using SoundFlower and SoundFlowerBed.app.