I've tried using transparency as part of my layering in my latest layout titled "Fun" in my family gallery. It's a very fun technique and it really creates a very different look to the overall look of the page with it's shiny surface.
In my layout, I've cut out a circle clear transparency and painted it's edges using some black acrylic paint. Then I've used a white paint marker to doodle on it. It does actually create the effect that I wanted so bad for my layout.