Need effect: caption text that modulates with sound level
 

This might sound like a strange one, but for a trailer that I'm making I need to show some caption text on the screen and then modulate it's appearance with the sound levels of the audio track. I kind of remember there being some way to do this in Final Cut, but I haven't been able to track it down. Any help appreciated.
Thanks
Greg

If you have the newest Motion it has a series of audio behaviours that you can use. Just create your text and then right click on whichever attribute you want to have driven by audio and then select audio from the behaviours menu.

Nate, thanks very much - I've been searching high and low.