Pulverize the rice using a metate y mano or your blender.  Grind the mixture as smooth as possible. Combine the rice with the almonds, cinnamon and lime zest. Stir in 2 1/4 cups hot tap water then cover and let the mixture stand overnight (minimally 6 hours).

Place the mixture in the blender jar and blend for at least 3 - 5 minutes until the mixture is smooth and no long has a gritty texture. Add 2 cups of water and blend again for just a few seconds.  Place a large sieve over a mixing bowl.  Line the sieve with 3 layers of damp cheesecloth.  Pour in the rice mixture, a little at a time and keep stirring to help the mixture go through the sieve.  Once all the liquid has passed through to the bowl gather the cloth together at the top, give it a twist and squeeze out any additional liquid.

Now add 2 more cups of water and stir in as much sugar as you'd like, to taste. If the mixture is too thick, add some additional water. 

Cover and refrigerate. The drink should keep several days, refrigerated.
Serve in a tall glass over ice.