Times they have changed since 9-11. Used to be a person could carry all manner of things on a commercial aircraft, but no longer. At least they've gotten past the initial hysteria when a person wasn't even allowed to take toothpaste or Chapstick in their carry-on. For a while there, knitting needles were a no-no. As my Mom wondered, "What do they think I'm going to do, knit an Afghan?" Needles are acceptable now - I always make sure to carry bamboo or wood instead of metal because you can never tell when they might go hyper vigilant on you. (Beware the Detroit Airport; TSA employees there tend to be excitable.) The security folks are still a little weird about anything with a blade, though.
So what's a knitter to do if she needs to cut her yarn (besides buy a heavy and kinda homely Clover yarn cutter pendant or gnaw it off like a wild animal taking care of the umbilical cord?)
The answer, my friends, can be found at local office and card stores.
Yep, the Scotch Gift Wrap Cutter. I got this two pack at Sam's Club for under $4.00. It looks like a toothbrush, but instead of bristles, it has a sharp little blade hidden behind an underslung jaw. It won't cut your fingers or your yarn flush with the fabric, but it does a great job of cutting while leaving a bit of a tail.
If you get a two pack, save one for Christmas. It works way better than scissors on gift wrap and it's safe for the kiddies.
(And, no, 3M is not paying me to advertise this, I just like to share things that work for me.)