Hi, I am having a rather annoying problem with my MacBook lately. Now and then I hear this "boing"-like sound. It's exactly the same sound you hear in Firefox when doing a search on a site (with apple-f) and the word you are typing can't be found. You can also hear this sound when copy-pasting a piece of text into a MacMessenger conversation window which exceeds the maximum length. It seems to occur at random intervals and I always hear the sound two times in a row, about one second apart. I am watching a movie tonight, and it has happened 3 times during the last hour. Applications running: Mac Messenger Transmission Quicktime iTunes Firefox Google Notifier (Dashboard: Indicate & iStat Pro) Any thoughts?