Here's an alternative: NOTHING.
Have you ever seen the Godfather, Part I ?
Everything these screeners catch can be smuggled in by the girl at the Dunkin Donuts in the terminal, and picked up by a passenger.
The fact is if people want to bomb a plane taking off from the US, they will bomb a plane. We can't prevent every possible plot, and the way we're going crazy about this is hammering us in other ways.
Here's just one example:
Camden NJ is laying off half of its police force.
Many other towns are also laying off officers, and that is far more of a risk to homeland security than airport screening. All this money going to catch tweezers and underwear bombs would be better spent giving to towns so they can keep their cops.