Nothing sharp is allowed at all. I've heard several stories of folks having safety razors confiscated our of their toilet kits.
I left PDX bright and early friday morning. Being who I am, I was hustled right past security, given a cursory inspection and escorted right onto the plane. Now, you might say, "come on chuck, being 'The Balisong Collector' might command a tiny bit of attention here, but how does that get you past airport security?" The answer is that it has nothing to do with balisongs and everything to do with the fact that I'm always late for everything. I was born two weeks late and I've been trying to catch up ever since. Anyway, I arrived at 6:30 for a 7:00 am departure. The line for the security check was at least a half hour long. I was so happy that the very nice fellow from Northwest Airlines just walked me right past it. Once we cleared our cursory security check, that young fellow looked at me and said, "Can you run?" I said, "I'll beat you," and off we went. Fortunately, the counter agent had called ahead and they were holding the plane for me.
Once aboard, the lead flight attendant announced, and I'm quoting as close as I can remember, "Once we reach our cruising altitude, we will be serving you our so-called breakfast. Each of you will receive a package of dry cereal, a bananna, and a bagel. You'll also receive a packet containing salt and pepper in case you'd like to season your bananna, a napkin, a spoon and a fork. You'll notice that the package is open since these packages were put together before recent regulation changes and used to include a plastic knife which has.... excuse me, I a now told that we now have new packages which are sealed and don't include a knife. Following the so-called breakfast will be our beverage service. Recently, several airlines have had to cancel flights and ground aircraft because passengers have found mysterious white powders. In all cases, these have turned out to be either non-dairy coffee creamer or non-sugar coffee sweetners apparently spilled by a previous passenger. Canceling flights and grounding planes is very expensive and very inconvenient both for the airlines and for passengers. So, we will not be offering non-dairy creamer or non-sugar sweetener today. Sorry."
Most of the planes I flew on were barely half full and all of the airline employees were very gloomy. The friendly skies are not very happy right now.