What kind of a person are you? What kind of a career would suit your personality? Are you an introvert or extrovert, do you focus on the present and concrete information or do you have an intuition and go by gut feelings while solving a problem? Are you ruled by the heart or head?
People's behaviour, feelings, actions, thoughts are varied and spread across the spectrum. To broadly classify people under different personality types Katherine Cook Briggs and her daughter Isabel Briggs Myers developed the Myers-Briggs Type Indicator which is a widely used personality test.
How it works?
The test is based on 4 type preferences.
Introvert (I) & Extrovert (E)
Sensing (S) & Intuition (N)
Thinking (T) & Feeling (F)
Judging (J) & Perceiving (P)
There are 16 types of personality, based on the 4 preferences, as shown below.

I had a "wow" moment when I took a test today and the results were pretty close to my personality. Here is the URL for the personality test. It has 69 yes/no type of questions. Shouldn't take too long to complete.
http://www.eggheadcafe.com/articles/mb/default.asp (Don't get mislead by the title. This test is not just for programmers.)
To make sure that the results were accuracte, I took another test which gave the same result.
http://www.humanmetrics.com/cgi-win/JTypes2.asp
Try the above tests and judge for yourself.
Who am I?
I am an ENTJ (Extroverted iNtuitive Thinking Judging).
ENTJ - Business executives, CEOs, organization founders, business administrators, managers, entrepeneurs, judges, lawyers, computer consultants, university professors, politicians, credit investigators, labor relations worker, marketing department manager, mortgage banker, systems analysts, scientists. They are born to lead and can steer the organization towards their vision, using their excellent organizing and understanding of what needs to get done.
Below table shows the population break-down on the different types.

What bothers is there are only 1.8% of ENTJ. It sucks to be in the minority. :(