And as Phil Plait points out, when you are primed with subtitles, it's very easy to hear something that isn't there. However, I would argue that the video that Plait links isn't really pareidolia. It's a real song, with actual lyrics that make sense. The subtitles merely encourage you to hear something else. In other words, the subtitles are an artificially induced mondegreen (given the title "auteur du mondegreen" here).
This video (via Greg Laden), however, shows what I think is real auditory pareidolia.
Actually, there are two different instances. The toddler has obviously been taught to perform (can you say child abuse?), but to my mind, the utterances are all late-stage babbling: there's an intonational resemblance to speech, but no actual words. Yet the audience appears to think he (she?) is preaching (pareidolia #1).
The second is the one induced by the subtitles, which are hilarious.
And where the subtitles say "I'm seething," I suspect that the reaction from the audience at that point ("Jesus") is their interpretation of the same thing. I originally heard "I'm sleepy" for that phrase, so there's pareidolia #3 for you.