During the Global IoT day contest, one of the projects mentioned was an Imp controlled beer/soda tap. I think this is a great idea, and wanted to start a thread for brainstorming. I’m going to list some features that would be really cool to have. A similar project exists at kegbot.org.
Features:
* Tap/dispensing control with servo/solenoid/ect.
* Glass sensor/scale (Would sense if a glass as under the tap and how full it was with tare.)
* Flow volume monitor - Track how much volume remains, how much is dispensed.
* Fridge temp & liquid temp.
* Keg low alerts
* Web/iOS/Android interface
* Select glass size for automatic pour
Of course, this project will also need an ePaper display! 
Vanessa is coming soon!
Assuming the keg is inside some kind of insulated box, how about sensing the temperature inside and out of the box and when the outside-the-box temperature is lower it closes a contact to run a fan to air-cool the keg till it reaches its target temperature.
If you used some kind of sensor that could go at the end of a long cable it’d give you the option of running a long vent to the great outdoors and put the sensor there. (though I guess you could get the outside temperature from a weather data feed).
PS Mmmmm Beeeerrr
I’ll be building mine inside a refrigerated tap, but there is some interesting temperature data to be gleaned there. If the temperature at the bottom of the keg is significantly different from the temp at the top, (where the tap lines are) you get a lot of foaming. I’ve installed a fan inside mine to circulate the air.
Vanessa is coming soon!