When my employer (U.S. DOE at Argonne National Lab) instituted "Safety" rules requiring all motorcycle riders on site to wear a helmet, I simply quit. Best thing I ever did!
http://www.olympiamotosports.com/phantom/phantom.htm here you go, you can wear this almost year round. probably at least in the mornings. i too work for DOD and need to wear business attire. i just wear leather in with chaps to protect my pants and if its warm leave them off. i have the suit and its ok....worked great this winter using it outside in the blizzard. works good on the bike too....get some airflow. a little expensive though. i'd wear it more except i'm a little big and i look like a "fat boy" in a snow suit.
I been thinking about riding to work as well. They look at our uniforms closely. (Im a LEO) One guy rides to work time to time in his uniform. I am not too sure I want to do that.