Walking along in the eastern part of the map on the way to Republic of Dave, there was a fireplace hanging in the air. At this point I wished there was a mod to identify which mod that fireplace belonged to. There was such a utility for Oblivion called FormID Finder, that would allow you to click on an object and get the info on which mod it belonged to.

Is there a similar utility for FO3? I know I can just disable it, but not knowing which mod did it will bug me.

if you were to activate the console then select the fireplace the first two digits should indicate its placement in the mod index then compare to FOMM's list should give you the offending mod