I took the following test before and I found it to be extremely accurate and far more meaningful in result explanation than most of the personality tests you come across:
Human Metrics - Jung Personality Test
There's 72 short questions to which you answer either yes or no.
It's VERY important that you answer the questions honestly, because there is no middle ground. It's yes, or no. If you can't answer a question with an acceptable amount of personal conviction, then just go with what feels right.
I'm telling you, if you do this test honestly, the result is dead on. And very insightful.
When you submit your answers, the following page will tell you your personality type and provide a couple sources of written analysis of your personality type, either of which you can post for comparison with others.