First, make some ice cubes out of tonic water.

Prepare a tall glass full of the tonic ice cubes.
Add the Gin (we like Bombay). Next add the Tonic water. Hit it with a splash of Cranberry juice, squeeze in the juice of one lime wedge and garnish with another.

It might seem like maybe there's not enough tonic, but with the cranberry and the lime juice, plus the "cube melt"... it's just right.

Perfectly refreshing on a summer afternoon or after a long day of work.

Variation: Use Vodka instead of Gin if you're into that.