Myer-Briggs Type Inventory
The MBTI is a questionable measure, although I like it myself. Ten years ago I consistently tested as an ENFJ, but at some point I made a life choice to be more analytical, hence, the change from E to I, and from F to T. Nowadays, I consistently test as INTJ, although the I is just over the midline into I, and the T is just over the midline into T.
As a developer, I love the more abstract (N) concepts, such as design patterns, and eschew concrete how-to's (S), but my work-oriented websites would indicate I'm ISTJ, while my blogs and personal sites would indicate I'm INTJ. This made me wonder if the demands of work result in the IT personnel tests skewing to ISTJ. Rather than tech people being unable to change, I'd guess that the world of work, e.g., business people doing the hiring, allows limited change and requires a particular set of traits.
The website used for the Type Analysis of sites: