I like my olive drab shemagh scarf.  The pattern works well with my camouflage, the cloth is supple yet definitely rugged, and it's quite versatile.  Larger than many bandanas I've had, I can do more with this scarf.  It's great for keeping me warm or cool, protecting me from the elements, biding and carrying things, or helping me camouflage things.  Draped over some of my gear, it helps break up telling silhouettes, and helps it blend in with surroundings.  Depending on your social circles, they can also be fairly stylish.  I'm quite pleased with this particular shemagh, as it feels of higher quality than the ones I got from a local outfitter.