I travel pretty much for a living, currently coming at you from the EU. I ALWAYS carry certian items. but it never fails for TSA to catch something.... but it just means they are doing their job, and I dont mind the extra searching one bit, but the last time thru SLC I was stopped and grabbed by TSA, they took my PC Bag and started going thru it, I asked what it was they were looking for. The guy said a grenade, I just shook my head and said it was in the front pocket but your going to be disappointed. It was a spares carrier from surefire. When full and looking down at it from a Xray I guess it looks like one, I would have guessed a revolver cylinder instead.

Items I always have on me. AMK/ doug ritter pocket survival kit, blades removed (added to checked luggage, with carry knife adn leatherman) water purification tablets and Immodiam AD added to it... so be it I have accidentally left the blade in there a few times with no issues, mag block, flint and striker, the striker is from a "light my fire" kit, the thing can shave the mag block with ease and be used as a crude knife if needed I guess. A surefire E2D with tactical night vision 220 lumen LED head and strike bezel. You will not see it coming. I wear a wilderness tactical products instructor belt. Get it swinging and the buckle will rattle your head or drop a jihad. I keep 50ft of 550 cord in the bag and @ 14 ft wrapped around my wrist as a bracelet. I carry a few MRE sides, "THEY" could tell me to toss them and I will, but have not ever been stopped for them. Also carry a bag of mountain house blueberries and granola (since it does not need hot water to taste good) and some clif bars. Last is the pocket version of the SAS survival guide.