The Lights of Zetar :
In the briefing room scene the Captain has a large pimple to the left of his nose.
There was a youtube clip being circulated a few years back of a command division crewman sealing off one of those fire hydrant looking things on the wall of the corridor in an attempt to seal everything shut and keep the storm out. We were all having a laugh because he apparently was empty handed pretending to screw the thing shut. Only thing is...he does have something in his hands! It's plastic or glass, but he's holding something to help him batten down the hatches.
In the final sickbay scene check out the door behind Bones. A rare bit of sloppiness as someone's just dumped what looks like a bunch of painters' sheets on the floor.