Since that first epiphany, I've made a point of having at least one encounter with laundry and laundering on every trip I take. Handing my dirty clothes to strangers, I seek clues and signs in the way they come back to me (in Bangkok, with little pieces of colored yarn attached to the seams, to distinguish my ratty cargo pants from the ratty cargo pants of every other backpacker on Khao San Road, I suppose). A button that disappears from my shirt at the hotel laundry in Shanghai appears, in a slightly mismatched reincarnation, years later, when my shirt pays a visit to a laundry in rural Japan.

Some friends of mine, recently back from a trip to India, experienced what must be the traveler's Laundry Holy Grail. A little while after surrendering a pile of dirty clothes to their guesthouse staff in Varanasi, they spotted their shorts and T-shirts spread out along the Ganges, being scrubbed and slapped by Varanasi's world-famous legion of dhobi wallahs, the local washerwomen and -men.

In Venice, I wandered away from the guidebook route and took many, many photos of old flowered tablecloths and embroidered pillowcases sagging from the windows of crumbling houses. The presence of hanging laundry, just about anywhere in the world, signals that you've left the manicured tourist zone and entered "real life." It gave me even more of a thrill to think that, dangling from a hanger outside the window of my tiny guesthouse, my socks had become part of the Venice laundryscape, too.

You know you're really traveling when you run out of underwear. I remember one bright morning, in Tonga, eating breakfast while watching my newly washed sarongs on the line flapping furiously in the breeze. I'd been away from home for weeks by then, and I didn't know when I'd return; my laundry was proof of how far I'd come, and how far I'd yet to go.

My fresh, clean clothes strained on their tether, as though aching to sail away on the warm South Pacific trade winds. And, I realized, so was I.