Whether or not you believe that the Myers-Briggs Type Indicator is useful (or a crock of s**t), it can be insightful (at best) and entertaining (at least).
INTJ: description here.
INTP: description here.
I came across an old and funny poll on a bitcointalk.org thread here.
If you haven't "typed" yourself, here is an unofficial questionnaire that may or may not shed some light on your "type".
Personally I have found that the most helpful section of results was an increased awareness of one's strengths and weaknesses.
 

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I'm one of those ENTJ's hanging around wondering why so much time is spent analyzing and so little acting! ;-)
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