Here is my in progress project of automatic cocktail maker, HardWino.
It's not an innovate concept as you can find a lot of similar projects, but the purpose of this tutorial is to offer a low cost and easy way to do an arduino based cocktail maker.

How it's works?
A touch screen with an Arduino MEGA allows to select your cocktail.

A first motor (a NEMA17 controlled by L298 driver motor) turns the rotative drink holder to the first bottle then a linear motor (still drived by a L298) press the valve during a determined time.

The first motor turn again for the second bottle etc etc. Once the cocktail is done, the first motor turn in reverse until activates limit switch.

Then you can enjoy your drink!

First part of the tutorial :