Once devoted companions to US soldiers during the American War, Zippo lighters tell unique stories through the messages and symbols carved into the lighters' metal casings. Be forewarned though: profanity is common in many etched messages; they were written by homesick, disgruntled, weary soldiers after all. Most Zippos still work and only require a top up of lighter fluid or a new flint. You'll find mostly copies in Hanoi, but the one Martin Sheen flicked in Apocalypse Now wasn't the real deal either. Faux War-period Zippos can be had for under VND100,000. Start your search around Hanoi's Old Quarter.
If you're shopping for a genuine War-issue lighter you may want to bring along a Zippo identification book to help you weed through the sea of fakes. Zippos were issued to the U.S. Army, Navy, Marines, Vietnamese Coast Guard and RVN, so you'll have plenty of stock to rummage. If you do manage to find a vintage authentic Zippo in good condition, be prepared to bargain hard. It's base economics; supply is dwindling and demand is rising.