Erin Liszewski of SmarterTravel.com posted a strong recommendation for WineSkin:
Some leftover foreign currency is burning a hole in your pocket at the tail end of a vacation abroad, and the duty-free shop’s siren song is calling to you. But after snatching up armfuls of discounted bottles of booze, the fear sets in. With strict limitations on the amount of liquid you can bring aboard both in the U.S. and abroad, how is your precious cargo going to make it home?
Never fear—you can make it through security unscathed. Plan ahead, and leave room in a suitcase so you can transfer your alcohol into your checked luggage when you get it from baggage claim. Bring along a plastic bag or WineSkin and wrap your bottle before padding it with clothes. Then recheck your bag after you go through customs inspections, and stroll through security knowing your liquids are safe and sound.