...if you email us and are #41. Subject should be #41, include your steam name, email only once. Anything other than that and if you happen to be #41 you won't win.
Today's key was won by StrongJoshua. He was the 41st person to send us one email with "#41" in the subject and his steam name in the body. Congratulations to StrongJoshua and good luck to everyone for tomorrow's free key (details here).