Insignias, Roundels, etc. by the boatload!

[John Howling Mouse]

Created with the freeware graphics program "Inkscape"
While many are actual military insignias that you're sure to recognize, several others would be great for What If subjects of all genres.  If you're into printing your own decals, here are some cool ideas.

http://commons.wikimedia.org/wiki/Category:Created_with_Inkscape