We signed up for the Global Entry, Trusted Traveler program about a month ago. http://www.globalentry.gov/howtoapply.html You have to pay a $100 non-refundable fee to apply. We figured that we travel enough, we would give it a try. You do have to go to a Global Entry airport, which required us to drive to San Francisco from Sacramento. We simply combined the interview with a trip to see the Dutch Masters exhibit at the De Young Museum. The interview itself took less than ten minutes.
Yesterday we got a chance to use our new status. We landed at LAX after our trip to Mexico. The line to see a immigration officer was LONG. We skipped the line and went to the Global Entry kiosk. The machine reads your passport, takes your picture and verifies your finger prints. Then it asks you a few customs questions and prints out a form with your picture. We then breezed through both immigration and customs. We were both very pleased with the expedited process and look forward to using it when we return from Europe in June.
If you are a frequent world traveler I would recommend this program.