I used to use isightcapture all the time on my ibook G4 with FireWire iSight. It no longer works with my MacBook; it seems to be confused between the built-in USB iSight and the external FireWire one. There's no way to tell it which one you want, and since I need it for an event webcam, the built-in (unaimable) camera is not a useful choice. I wrote to the developer about a year ago, but never heard back. It's a shame, because this used to be a nifty utility.