I am fortunate to work in an industrial environment where the dresscode is jeans and a polo shirt. It is no problem to walk around with a Leatherman on your belt, a folding knife clipped to one front pocket and a high output EDC flashlight clipped to the other pocket. However many of our friends here at ETS must meet a more stylish dresscode and having a SureFire sticking out of your pocket is a no-no.
I work in a business casual office. I've always dropped the heavier stuff (mini-mag, pocket knife/MT, etc.) into my business bag. Either one of the outside compartments or the organizer section. I keep a mini-LED (Princeton Tec Pulsar II) on my keyring for the usual power outages.