I discovered this site for stampscapes a while back. While I love their stuff, their shipping charges are too much for me, so before taking the plunge and buying a bunch of stamps (to justify the shipping fee) I tried their paper saturation / 'painting' techniques to make a card and then use stamps I already own.
I used make up sponges to apply the many layers of ink on glossy paper, then stamped over it all with the closest silhouette stamps I had. It didn't quite work (and I tried using a marker to increase the silhouettes, which was a mistake - the lines show up darker than the stamp ink, so it looks strange) but I can see myself trying this again when I have more time. I haven't mounted it on cardstock yet, but I except I'll do so on black or dark blue.