Here is a neat little trick i just discovered. These designs are just done using the Inkscape spiral tool, and a dashed stroke! Once you try it out, be sure to leave a comment showing off your spiral design!
How it is done:
Step 1. draw a spiral using the Inkscape spiral tool, and add more turns to your spiral (i changed from 3 to 20):
Step 2. In the fill and stroke dialog, choose the Stroke style tab. Then bump up the stroke width (i chose 7px), and change the Dashes to something non-solid.
Step 3. Experiment! change the stroke width, dash style, and number of turns of the spiral:
If you want to see the settings required to make the above designs, download the SVG from the openclipart library