Many components in the GNOME desktop use libcanberra-gtk to play sounds, which has led us to a wonderful world of positional sounds (in many cases), where a sound seems to come from the same direction as an interaction on the screen.

Metacity uses libcanberra for audible bells, so it is pretty straight-forward to get the same feature. In my opinion, it would make Metacity's bell sound suddenly awesome, for a number of reasons.

To implement the feature, Metacity needs to give a few extra properties to Canberra, which describe the position of the window associated with the bell.

Patch is attached. I look forward to any feedback!
Some usability analysis may be a good idea, too. I think positional sounds have tremendous benefits for usability, but there could be some other viewpoints out there :)