Not what we would usually think of pertaining to maps but there are 2 places this could be used:

1 as map elements/set dressing to put in the corners of a map for decorative purposes
2 making elements for dungeon/structure scale to fill our dungeons with

I like the idea and it would be kinda cool to "take a lil time off" from actually drawing maps and do something different and fun. I've never actually drawn just armor but I have drawn people wearing it and fighting monsters in it. I also think that maybe you could include phasers for the sci-gi guys and maybe some Lugers for the alternate earth guys. Depending on which way it goes then I think a full set of icons would be good for number 2 and more artsy stuff would be good for number 1.