Nope, Tom... they won't let me take my mop and broom with the 83 death-dealing devices... 84, if you wish to light a cigar!
I get to do drawings for facility planning at the Boeing plant. Need a desk moved here? How about reconfiguring the lab for a new project?
My previous job that required a security clearance a few years back involved measuring every room and verifying the configuration of the Alternate Joint Communications Center inside Raven Rock Mountain in Pennsylvania (
http://www.fas.org/nuke/guide/usa/c3i/raven_rock.htm), near the Maryland state line. It's essentially the alternate Pentagon; all communications for the Defense Department are routed through there. While I can't go into specific details about the site, it was pretty interesting work. And the chow was good.