Need something mailed to you on a trip, but between hotels and not sure when your post will arrive? Want to send some stuff in advance? If you've got an American Express card just track down the local American Express Travel Office at your destination, give them a call and arrange to have things sent there.
The little-known service is available to all American Express cardholders across all issuing countries, and is not restricted to Platinum or Centurion members.
The official name of this service is Client Letter -- and, as the name would imply, it's meant for letter-sized mail only. However, we've used several offices in New Zealand, China and the UK that are intent on pleasing their customers and are happy to receive small to medium packages.
We've used Client Letter for packages from documents to small electronics (cellphones, memory cards and so on) and it's always worked for us. Don't expect to be able to mail your full trade show kit, stand and all, but smaller items should be fine.
Using an Amex office as a mailing address is particularly useful when dealing with the increasing number of online merchants who won't ship to a PO Box.
Top tip: if feasible, have "Amex cardholder" as part of the mailing address (perhaps under or after your name) to help the person in the office figure out that it's your mail and where to store it for collection.
Officially, Amex says that items will be held for thirty days, which should be long enough for most users of the service.
American Express Travel Offices are also incredibly useful if your cards and wallet are lost or stolen while abroad. Amex is one of the few credit card companies that will create an emergency replacement card in many of its international offices, including at many airports.