I know that on the creative cow site a couple of years back there was a great tute for this.
A look I like is duplicating your media on another track, use the Overlay mode in the track composite modes on the top track, add a nice healthy glow and drop the opacity about 25% - then add the black and white fx to the lower track and drop it to about .800 - not exactly bleach bypass but a nice, contrasty, soft look with muted colors.