Sorry, not sure where to put this. I've been getting a strange mail every once in a while. A "notification" from "Lordaeron" is what it says, but it looks to contain a small brown bag for c.o.d. (2000g). I don't even open it because it seems sketchy. Anyone else?
Basically what they will do is give some ******ed excuses (usually says something like : "Hey, here is the gold I borrowed from you!") and send an item with C.O.D. How C.O.D. works is pretty simple; you send an item to someone as C.O.D. and if that person claims the item, his gold (amount specified by the sender) will automatically be cashed out and sent to the sender.
So basically, if you mindlessly go through your mails, click on this mail, claims the item (it will ask for confirmation, however.) then, your gold will be sent to this person automatically. In your case, it would be 2,000g.
Cash on delivery (COD) is a type of transaction in which the recipient makes payment for a good at the time of delivery. If the purchaser does not make payment when the good is delivered, then the good is returned to the seller.
It is used to trade with people that is offline without using the Auction House. There's people that always send herbs, cloth or leather to the same buyer. And yes, it is used to "scam" people that do not speak good English.