I made this really nifty graphic illustrating the Classical-Vernacular Spectrum in Keynote:
Here's how I did it: I needed to be able to import little images with transparent backgrounds so that stuff behind them comes right up to the edge of the image. But try as I might, no amount of copying and pasting through PhotoShop would make it work. In every case, pasting from PhotoShop resulted in a rectangular image where everything outside the image I wanted was white. Imagine taking each of the images above, drawing a rectangle around it, and filling in with white. In any case, on a whim, I grabbed the PhotoShop file in the finder and dropped it into Keynote. Presto! That worked!