I just used this 75% off code - CRLSB4 - from post #9886 [Apesmom], for "Gaslight Arcanum: Uncanny Tales of Sherlock Holmes."
...so I bought the darn thing! 
Since my account was set up as a UK account (and I live in Peru), the savings went from 3.13 pounds down to .90 pounds.
Translated, that means I got the book for $1.49
At Amazon, the price is $4.99
My credit card is a US-based card, with a US bank.