I always liked the Briggs-Meyers test. Through various work related courses, took the test about 4 times in total. The most interesting one was the one where we took the test, worked on a problem in a video taped meeting, got the results of the test and the predicted roles in the meeting. We then watched ourselves in the meeting and the predicted roles we took were just as predicted. I think this was a very effective way to demonstrate how different personalities work together in action. The course was a 2 day "Effective Team Membership" course. Don't know if there is any courses similar to this one offered, but I would definitely recommend this if it was available.
The last test I took was a little more detailed in its results. In this test, I was listed as a IENFP. I had assumed my previous results meant I was on the line between Interverted and Extraverted, but the other test said I was the extreme of both an INFP and ENFP. Made a lot of sense as I could never figure which of the two to choose.
