This one is more for web sites. I created this and give permission for anyone to use it for noncommercial purposes.

This is a circle divided almost evenly vertically by an arcing line to form the letter D. The lines are drawn with a flat split nib pen that fades on the left side of the circle.

This is a circle divided almost evenly vertically by an arcing line to form the letter D. The top of the arc forms a loop. The lines are drawn with a flat solid nib pen.

This is a circle divided almost evenly vertically by an arcing line to form the letter D. The top of the arc forms a loop. The lines are drawn with solid lines of even width.

This is a circle divided almost evenly vertically by an arcing line to form the letter D. The top of the arc forms a loop. The lines are drawn with solid lines by a flat nibbed pen. The line of the circle fades on the left side of the circle.

Now for the mom mobile test…

[ferrari f430 scuderia spider 16m]

And the My Little Pony test…

[ford mustang GTR]

That works.

UPDATE:
After trying on a lot of different symbols representing Deism, I finally settled on the “flaming D” you see on the top left of this page. For more info see: <http://www.amorian.org/2009/07/30/new-and-improved-deism-symbol/>

Stumble it!