It's the end of September; it must be time to read a new Discworld book! This time, Moist von Lipwig takes on the Royal Mint -- so if you liked "Going Postal", you'll probably like this. (If, on the other hand, you didn't like "Going Postal", then -- well, it's a Discworld book, you're probably going to buy it anyway, right?) It's no "Night Watch", but it'll do.
ISBN 0385611013.