N95 type dust mask.
Kendall 1" waterproof tape
Gauze
Advil
Aspirin
Bonine
Leatherman Micra
Passport card (the one that looks like a drivers license, costs $10 on top of the passport fee - only good for land crossings but contains all pertinent info)
Xerox of all documents kept separate from documents
Amex/Visa/Mastercard
U.S. dollars in uncirculated condition (yeah, condition matters a LOT in some countries)

Above and beyond that, very downmarket looking luggage and clothing. If you want to make yourself a target, get that Louis Vuitton luggage set and as much rap-inspired bling as you can, tell the mugger hello.