Recently, I have been obsessing about Myers-Briggs personality typing. As someone who is fairly clueless about what makes most people tick, I have found this to be very helpful in understanding others and myself. It's true. I am a weirdo. My personality type (INTP) is rare, especially in women. I used to assume other people were just better at hiding their difference.
Here are some links to find out what your Myers-Briggs type is and find out more about it. If you have a personal relationship with me, I will probably ask you what your type is at some point. Now, there is no excuse not to know.
Take The Test Here. A few pages with better type descriptions are listed below.
Typelogic.com Brief type descriptions and information on how to join mailing lists.
Personality Page More detailed decriptions, including an explanation of why you're so hard to get along with. My all-around favorite.
The next set of links discusses interactions between basic types. I've listed them separately to spare everyone the sales pitches:
NT and SP
NF and NT
NF and SP
SJ and NF
SJ and NT
SJ and SP