lemon drop martinis and other favourites

The warm weather is finally here and with that comes the cocktail parties on the patio. I have my mini lanterns, tiki inspired furniture and the cocktail attire all set. Now I need interesting recipes. Every year I try to experiment with a new summer drink. Last year was lemon drop martinis (still a favourite), I think this year it might be capirinas. For some reason it is hard to find cachaça, the Brazilian sugar cane liquor but I was able to substitute with white rum. Still very good. What are your favourite summer cocktail recipes?