You'll have heard these before, but in case you haven't, New Scientist have collected five interesting audio illusions. (Thanks, Ben)
Posted by Tom Whitwell.
Hm. On the left/right-handedness thing, I actually hear both melodies in both ears, and I can also hear them ping-pong between the ears. I do have a tendency towards ambidominance, though (although I'm generally right-handed I don't have a dominant eye or foot, and I think my right-handedness is just because I've generally been taught to do things with my right hand).
Relatedly, in the arpeggio one, I can hear the melody even in the really slow version, but then again I'm a musician and I tend to use a technique like that when I compose a lot of my songs, so I'm probably a bit biased against hearing it.
The "phantom words" one was pretty interesting though. The phrases I heard most were "no way" and "we'll wait," neither of which were listed on their common list. It was also pretty weird how I didn't hear any words at all through headphones... the widely-separated speakers really were important to the illusion.
The stereo/binarual phonography one is still a lot of fun. Someday I want to get a binaural phonography rig and record my music that way.