[plt-scheme] Looking for Psychology lab applications

I am wondering if anyone has developed a module to support (or complete 
applications/demos for) a sensation and perception lab suitable for 
psychology undergraduates.

In particular, this would include sound support.  I couldn't get sound 
working on linux around version 207, but maybe support has been 
improved since then (or it has been working all along and I had a 
config problem of my own)?  For what it is worth, I think the folks in 
Psych who would want to use such tools have macs.

Thanks for any guidance,
--Wayne