I always learn something from the Transportation Security Administration's blog, mostly the staggering number of contraband grenades, handguns and bullets that are confiscated each week during routine airport security screening.
For starters, Christmas crackers, something more commonly found in Britain, are prohibited. I'm not traveling by air this holiday season, but if I were I wouldn't have thought twice about putting a few of these in my hand carry. The festive crackers aren't the kind you eat but the kind you pull. (For the uninitiated, they make a big pop, spewing confetti or little prizes that were tucked inside.)
And it's the pop that's the problem. It comes from striking a chemical strip, the way cap guns work. Britain's airport security bans them too, identifying them as party poppers.
Another item sure to get confiscated: CO2 cartridges. These come in home soda machines that you might receive or give as a gift. They're what puts the fizz in seltzer and other soda-type drinks but are prohibited anywhere on the plane. So check before you bring one along; TSA recommends shipping it instead.
Little snow globes (really small ones with less than 3.4 ounces of water) are allowed if they fit in the same plastic bag you use to stow other liquids.
So now you know. Happy traveling, happy holidays!