All emotions come from the subconscious. Fear, anxiety and all the other emotions a person experiences are the direct result of the subconscious mind operating. This is why emotions seem to come out of nowhere (See why do we have emotions).
Respiration, heart-beat, sweating and other involuntary body functions are directly controlled by the subconscious mind. While some of the those functions can be consciously controlled, most of the time they are still controlled by the subconscious mind.
The subconscious mind is the place where beliefs are stored. The beliefs a person holds about anything reside in the subconscious mind. This is why some beliefs can't be changed easily even if they are illogical. (example: irrational fear of darkness).
The subconscious mind is the place where memory is stored. All the events that a person goes through are stored in the subconscious mind in the form of memory.
Most dreams come from the subconscious mind. Some theories state that dreams are nothing more than the loud thinking of the subconscious mind (See how to interpret dreams).
The subconscious is the autopilot for many unconscious habits. For example, after some time, driving becomes a habit that a person rarely consciously thinks before stepping on the brakes or changing gears. The subconscious mind is responsible for the autopilot mode that controls many of our habits.
In most cases the body language of a person is directly affected by his subconscious mind, unless he decides to consciously control it.
Love and hatred are two examples of the emotions the subconscious mind controls. The gut feelings we get as soon as we meet a person usually come from the subconscious mind's past experiences and beliefs.
While the conscious mind is responsible for anything that we consciously notice, the subconscious mind controls everything else. Adding two numbers together to get a result will be done by the conscious mind, but feeling anxious before a presentation can be attributed to the subconscious mind.
Motivation can only happen when the subconscious mind believes that the energy spent won't be wasted. When the subconscious mind believes in something it can easily motivate you to do it. This is why so many people fail to motivate themselves using logic.
The subconscious mind uses emotions to direct people to important things. If, for example, you have an important exam in a few days then your subconscious mind might make you anxious in order to motivate you to study.
Because the subconscious mind stores beliefs, controls behavior and emotions, it greatly determines who a person will become. This is why the best way for a person to change is to target his subconscious mind and not his conscious mind.