It's actually hard to do that - I ran into the same issue with a site I made. There is no good way to play sound in a browser except via flash.
So I used a hidden flash applet and triggered it via html events. But the flash itself was hidden since it didn't have a UI - it was just for playing sound.
Since it was hidden there was no way to click-active it for flash block people.
Maybe I could have put a message of some kind saying flash wasn't active, but it didn't seem worth the trouble. (In my case sound was nice, but not that critical.)
So I used a hidden flash applet and triggered it via html events. But the flash itself was hidden since it didn't have a UI - it was just for playing sound.
Since it was hidden there was no way to click-active it for flash block people.
Maybe I could have put a message of some kind saying flash wasn't active, but it didn't seem worth the trouble. (In my case sound was nice, but not that critical.)