I knew I'd taken one last year sometime (it was almost exactly a year ago) -- I was an INFP in that one. Today I'm INFJ -- not sure what the difference between the two is, but I think I'm a little more cynical/impatient this year (he-he). Anyway, what I find most interesting about these tests is the profiles.
The overall idea about the INFJ is that we're supposedly very intuitive -- to the point, even, of ESP or other such phenomena. Now I truly am very perceptive. My mom said it used to freak her out a bit how I could always tell what people were really like, even when I'd just met them. Certain attributes jump out at me when I'm with people, and I can definitely get a 'sense' of almost everyone. INFJs make up less than 2% of everyone who's taken this test -- that amazes me! I mean, I know I'm unusual, but...;)
The funniest part of the test? Knowing that I'm 44% introverted -- DH still thinks I'm a complete extrovert ("Anyone who can talk to a complete stranger for over an hour has to be an extrovert" -- well, that or completely bored and wishing to get home to my book ;).