This probably is one of the "You had to be there" story
One exercise (Joint Winter 04) we had a small hq where all our pre mission planning would be and the squads that wasnt on a mission would wait. We are a quite small battalion and have not much stash to hide. Just some small tents actually.
Anyways at the start of the exercise the artillery battalion hq came rolling into our courtyard and sat up there gear, m113s and some other tracked vehicles. They probably used half a day to hide these under camo nettings and small walls of snow. When they where done we all thought "nice job, we even got free guards and defense"
Then we noticed a red and yellow flag at the top of the highest antenna....