I just posted a small set of mutant map icons to design graphical adventure maps over on my blog.
http://aeonsnaugauries.blogspot.com/2011/09/map-mutants.html
Those that might have missed my post here last month might also be interested in
theese post apocalyptic hex map symbols:
http://aeonsnaugauries.blogspot.com/2011/08/post-apocalyse-hex-map-graphics.html
http://aeonsnaugauries.blogspot.com/2011/08/more-post-apocalypse-map-graphics.html