We've all heard of the Big Mac Index or the latte index – using global products to compare the cost of living in various cities and countries against the US dollar.
But what happens to your purchasing power parity when you've arrived at a hotel late at night, absolutely starving and looking for something familiar?
As a favourite late-night room service order for business travellers after arriving on an evening flight, the famous club sandwich is as good a measure as any.
And Hotels.com has been doing the measuring at 1000 hotels in 26 countries around the world.
(The figures Hotels.com quoted are in US dollars, but since the greenback and the Aussie dollar are nearly at parity again, the difference is small change.)
So how much will you be expensing for those three slices of bread, chicken, bacon, egg, lettuce and mayo?
"Un sandwich club" will set you back the equivalent of $33.10 in Paris, the world's most expensive city for a sandwich.
That's almost exactly double the price in New York -- $16.93. Tokyo's almost as pricey as Paris, at $27.65 (or just over 2200 yen).
You might be surprised that otherwise-pricey Beijing comes in under the average at $14.48 (around 91 kuai), while London's clubs come in at $18.71 (or 12 pounds sterling).
And closer to home? Canberra comes in at the eighth most expensive city in the world for a club sandwich, at $20.
Here's that index in full -- just click to expand it.
What hotel food charges made you gulp in surprise? What's the most outrageous travel surcharge you've encountered? Sound off (and commiserate) with your fellow AusBT readers in a comment below!