With iPhone 4S and Siri, you will never be embarrassed because you don’t know currency exchange rates. Consider this scenario: You're on the phone with a hotel in Paris, France, and the desk clerk wants to know if you want the room for two hundred euros (€200) per night. Problem is, you have no idea how much that is in American dollars.

You could open up your web browser and try to find the answer while the Frenchman snobbishly sighs on the other end of the line, awaiting your prolonged reply. Or you can politely put him on hold for a moment, ask Siri for the answer, and tell him "yes" faster than he can say "coq au vin."

Here's an example of how Siri can help with currency conversion:

1. Press and hold the Home button.

2. Wait for the chime and begin speaking.

Sticking with example scenario, you could ask Siri, "How much is 200 euros in American dollars?" Or you can ask for "U.S. dollars."

Siri displays the answer for you visually, and even shows you exchange history and other currency exchange examples if you scroll up.

Ask Siri to convert from one country's currency into another.

You can even shorten your question to Siri. Because the iPhone 4S is location-aware, you can even ask, "How much is 200 euros?" and it'll automatically convert it to U.S. dollars for you. Or you can flip around the question by asking, "How many dollars is 200 euros?" If you're in Canada, it'll give you the conversion to Canadian funds, and so on.

Siri gets her information from Wolfram|Alpha — one of the world's leading sources for expert knowledge and computation. Whether you want to know what the Family Guy TV show is all about, who won the World Series in 1990, or need to figure out how much to tip the waitress at your local restaurant, the answers are just a quick question away. If Wolfram|Alpha doesn't know the answer, Siri will suggest a web search. To see what hoops you can have Wolfram|Alpha jump through, start with some fact-based basic questions and answers.