Vesper Martini

3 measures Gordon's Gin

1 measure vodka

1/2 measure Kina Lillet

Shake it very well until it's ice cold and serve in a deep champagne goblet with a large thin slice of lemon peel.

The above is Ian Fleming's recipe from Casino Royale. You can substitute Lillet Blanc or Dry Vermouth for Kina Lillet - in which case add a dash of Angostura bitters. Personally I prefer Bombay Sapphire to Gordon's.