Navigating Your Way through Trusted Traveler Programs
Frequent fliers now have several options from which to choose when it comes to expediting their way through security lines. The newest of these programs is Clear, which is privately operated but sanctioned by TSA. I recently became a member, and so far, it's been amazing. The one drawback is that it's only in 20 airports right now, but if it happens to be at your home airport, I think it is well worth the cost, and some airlines are offering discounts for the first year of membership. I've used it four times now, and each time, (either via my fingerprints or an iris scan), I'm through the line in seconds. Also, the program is available at several baseball stadiums and is still expanding.
The NY Times just printed a great breakdown on each of the programs, what the cost is, and what type of traveler is best suited to each program. Here's the link to the article so you can determine which program is best for you.