What mammals' milks are drunk by humans?
Add to this answer...  Who and where, what it tastes like, how it differs, how it's used in cooking...

Human

Where: Worldwide  

Uses: Nursing

Cow

Where: Most common source of dairy worldwide  

Uses: All dairy products (milk, cheese, yogurt, etc.)

Goat

Where: India, Bangladesh, Africa, France, common across Europe.  

Uses: Milk, cheese

Sheep

Where: Across Europe  

Uses: Primarily cheese

Camel

Where: Middle East  

Uses: Milk

Note: Camel milk can be an important source of water in extremely arid climates or survival situations.  The milk can have a salty taste due to camels' high consumption of sodium.

Yak

Where: South East Asia, Mongolia, Northern China, Tibet, Nepal 

Uses: Milk, Cheese, and butter; localized dairy products such as dahi, paneer

Water Buffalo

Where: India, Parts of the Middle East, Southeast Asia, China, South America, Europe (best known in Italy and throughout the Balkan states)

Uses: Milk, yogurt, cheese (mozzarella and others), candy

Note: Water Buffalos are the 2nd most common source of dairy in the world.

Horse

Where: Mongolia

Uses: Kumis (lightly alcoholic fermented drink)

Donkey / Ass

Where: Mediterranean countries  

Uses: Milk, yogurt, cosmetic and medical use

Reindeer / Caribou

Where: Scandinavian countries, Mongolia

Uses: Cheese, Butter

Note: Reindeer milk is 22% butterfat and produces extremely rich cream cheese which Lapplanders sometimes use in coffee rather than regular cream.  

Moose

Where: Russia and Sweden  

Uses: Milk, limited cheese production