I had been using the demo version of this software but I have now upgraded to the "real" thing and it is worth a quick review.
What is audio hijacking? Basically it is the ability to capture audio data that is being processed by your computer and writing it to a file such as an mp3 format.
Why would you want to do that? Well, the most logical use would be to capture an internet broadcast and save it for listening at some future time, just like making a video of a favorite TV show. But it could also be used to hijack sound from a movie DVD, or from a news broadcast. With an iPod available, this makes listening to internet radio possible when far from a connection. The sound file could also be burned to a CD for playing on a regular sound system.
How does it work? Well, the guys that wrote the software know the answer to that question, but the workings are quite simple, just like a VCR! And you can also use a timer to schedule the recording of a show, again, just like a VCR.
Of course, it helps if you hit the record button at the start and the stop button at the end. Actually getting this right is just about impossible, so the best method is to record more than you need and then edit out the beginning and ending surplus within iMovie. This takes a while to accomplish but is worth it if you want to archive the file as an mp3 in iTunes. Pete explains some of the machinations here.
Audo Hijack Pro has some neat bells and whistles which I have yet to understand, never mid try out! But it is definitely another piece in my multimedia puzzle and it fits!