Ah, the age old bandana . Well, hopefully yours isn’t ages old or at least I hope you washed it once or twice. I’ve found there are two camps out there, those who travel with a bandana and those who are completely disgusted by the thought of using one.
When I travel I typically take two bandanas and I wouldn’t go on any trip 100 miles from my house without both.
The first bandana is for good old nose blowing. And that’s ALL it’s for. It is color coded brown for “boogies” and remains in my back pocket while I travel. It has no other purpose other than snot and is sometimes referred to by that name, “snotrag”. 
I used to scoff at the idea of a snotrag until my wife explained how useful it was on a trek in Nepal. Carrying tissues creates a resource problem and not a ‘save the trees’ type of problem for me. I mean, it’s hard to judge just how many tissues you’ll need for any given trip. And buying more? Forget about it, it’s just a hassle. It’s much easier to find some place to quickly wash a rag every few days.
The second bandana is used for general purposes, such as sweat wiping and sun shading. In one of my profile pictures, featured here, you can see the utility in keeping the sun off my neck. And that’s what I’ve used it for a lot, both front and back. My last two trips to Peru and Nepal involved quite a bit of sun at times and with the help of the bandana I never got sunburnt on my neck (I used sunblock as well).
I have also found them to be very useful for that other age old use, keeping trail dust out of your throat. While I don’t ride a horse, on 4×4 or hiking trips in dusty areas the bandana does a wonderful job of keeping dust out or even warm breath in on those sub-freezing trips.
And I’m not sure why REI.com lists them as “Women’s Accessories” on their site as the links here indicate. They are handy for anyone traveling pretty much anywhere.
Do you have a particular handy use for a bandana while traveling? Share your use in the comment section below!
I bring one, but mostly use it for my head. I’m bald and burn easily. A bandana works great to cover it. A hat is often too warm when hiking and is more difficult to clean. A bandana works perfectly.
The handkerchief idea is kinda gross, but I can see why it would be useful on an extended trip/expedition.
Bandannas are useful but I think an equally good product are the Lightload Towels http://www.ultralighttowels.com. They are lighter than bandanas, easier to carry and more absorbent. You can also wick water away in the cold to insulate you. The packing protects the Lightloads until ready to use.