The Violet Hour's Rangoon Fizz comes to mind -- it's like a gin gin mule, but better.
1.5 oz gin (Plymouth or Bombay Sapphire work nicely, so do either of the North Shore gins)
3/4 oz lime juice
3/4 oz ginger syrup (to make ginger syrup, either combine ginger juice and sugar in a 1:2 ratio until dissolved, or just cut up a bunch of ginger and heat it with some simple syrup.
6-8 mint leaves
Premium tonic (Q or Fever Tree -- substitute Schweppes/Canada dry at your own peril)
3 dashes Angostura
Directions:
muddle mint with lime juice and ginger syrup. Add Angostura and gin and shake vigorously with ice. Pour into a highball or collins glass and top with a couple ounces of tonic. Stir to combine and garnish with an additional mint spring.