The souk in the Egyptian city of Aswan is as relaxed as its sleepy, Upper Nile location. Laconic salesmen try to tempt you into their premises with some good-natured banter: "I don't know what you are looking for, but I have it in my shop"; "Today everything is free"; and "I pay you to look in my shop".
But the real money is made by a large lady of advanced years, clad in black, who spends most of her time sitting in the shade against a wall the colour of old parchment. Only rarely does she get up, to waddle across and accost tourists -- picking out a family.
She makes a cursory attempt to sell a shawl. When you politely decline, she changes tack and presents a problem: she has been paid some euro coins and needs to change them into Egyptian pounds. But the bank, like banks everywhere, is reluctant to take foreign silver.
Look, she's holding out five €2 coins. Could you help?
Being a well-intentioned tourist, you agree to change them. But for how much? You guess that EG£7 to €1 is about right. Thanks to the conveniently round number that she needs to change, 70 seems fair. She appears to agree. You fish out a 20 and a 50 pound note, which she takes, but then demands 10 more. "Eighty!"
Your mood changes, which is an essential element of the scam. You turn to your spouse and children to express exasperation that someone for whom you were doing a favour seems intent on taking advantage of your benevolence. They nod sympathetically.
You turn back to her to demand your 70 Egyptian pounds back. She hands you a 20 and a 50. Only later do you discover that, while your attention was elsewhere, she has switched a EG£50 note for a 50-piastre bill. They look similar, but the former is worth around €7, the latter just 7c.
She has EG£49.50 of your Egyptian pounds, and still has euros in hand for the next victim.
Con artists across Egypt must rejoice every day that the government keeps such a low-value note in circulation, while honest locals despair at the sight of yet more disgruntled tourists.
There are few countries where tourists feel quite so pestered as Egypt. Visiting the Pyramids can be tedious in the extreme. From the moment you step out of your tour bus on to Giza's dusty plateau, you will be subjected to the constant : "Hello, my friend, where are you from?"
As welcoming as these chaps may appear, they only want to rip you off and get your cash, so keep your focus on the oldest wonder of the world and walk away.
Ignore any unsolicited offers from locals, as they will invariably result in you being scammed. And if you do end up a victim of the crooked currency scam, don't spend time arguing. Just threaten to call the police and they should hand you back your money straight away.
Con merchants dread having the police on their backs, so stand your ground and find the nearest officer.
Sadly, in this part of the world, you have to be extra wary of friendly strangers in your midst.