I followed the link on GMBMFB (you can too!) and took the test ... I came up INTJ.
A link to a description of that personality type describes me as a "Mastermind":
Masterminds will adopt ideas only if they are useful, which is to say if they work efficiently toward accomplishing the Mastermind's well-defined goals. Natural leaders, Masterminds are not at all eager to take command of projects or groups, preferring to stay in the background until others demonstrate their inability to lead. Once in charge, however, Masterminds are the supreme pragmatists, seeing reality as a crucible for refining their strategies for goal-directed action. In a sense, Masterminds approach reality as they would a giant chess board, always seeking strategies that have a high payoff, and always devising contingency plans in case of error or adversity.
Interesting schtuff. Another description is also keen.
What'd you come up as?
More detailed breakdown:
INTJ, Strength of the preferences %