I spent a little time cleaning up a celtic knot I really like from a clipart book and did a couple versions. The stained one is a straight raster carved at the lowest quality...the second has some draft applied and was carved on normal (Thanks Jason for the tip).
I've been playing with different stains on one project. This has some dark walnut around the outer ring, and a "flame mahogany" in the center..the outer edge and top is just shellac.
Man this machine is a blast.
http://home.mchsi.com/~dhaffner/keltic_knot.jpg