See below for the internet test and comments that spawned this post.
I am not a "joiner", I hate nametags and "personality tests" and hate people labeling me. That said, the real version of this test is pretty accurate, at least in my case. This is the short, official description of my type:
Have original minds and great drive for implementing their ideas and achieving their goals. Quickly see patterns in external events and develop long-range explanatory perspectives. When committed, organize a job and carry it through. Skeptical and independent, have high standards of competence and performance – for themselves and others.
My mom and I (ultimately/eventually--I was 11 when I first took it, okay?) found it to be very helpful in understanding each other. Initially, I think it was just nice to know that we had problems because (as previously stated I was 11 and therefore a freak and hated myself and everyone else) we actually were different and then how we were different and could find ways to understand and communicate with each other.
The Myers-Briggs Foundation
P.S. If you're interested, here's the description for the type that internet test chose for me. I have always been on the line between the two types:
Seek to develop logical explanations for everything that interests them. Theoretical and abstract, interested more in ideas than in social interaction. Quiet, contained, flexible, and adaptable. Have unusual ability to focus in depth to solve problems in their area of interest. Skeptical, sometimes critical, always analytical.