Siri offers some great functionality. However, there are some limitations on what Siri is able to do. By taking advantage of the Siri-to-Safari feature, you can use Google to look up things Siri cannot.
Sports scores – Look up the current score for in-progress games and find the team record, last game score, and the upcoming game. Say “Yahoo team name score”. Rydal points out “There is a ‘Yahoo’ here because mobile Yahoo formats the results better than Google.”
Flight Times – Say “Search the web for flights from City/Airport to City/Airport“. In Google, this brings up a list of flight times that day and the associated airline.
Movie Times (and Ticket Purchasing) Say “Search for Movie Name showtimes Optional ZipCode“, or if Siri will let you, you may get away with simply “Movie Name showtimes Optional Zipcode“. You can also “Search for showtimes Zipcode“.
Currency Conversion – Say “Search for 150GBP in USD”
Local Search (for non-US iPhone users) – Say “Pizzeria 12247” (German) or “Kino 12247” (German)
This will give you a list of restaurants or movie theaters in your area, in this case 12247 stands for Berlin.
Check out the help page at google.com for more search commands.