just my shrink 5 cents in here.
I sometimes do such tests for fun, but I wouldn't put too much value in their results. Why?
Most of them sound plausible, because the evaluation you read in the end is highly general and describes most of the population. So basically, you really have to be an "odd one out" to feel it is absolutelly wrong.
As an example, let us take the first sentence Maebius got> "Is sensitive and easily influenced by other's thoughts and emotions. Looking for friendly, easy-going relationships and jobs that help develop them."
Now think it over...how many of you would call themselves unsensitive, hard types who don't care about other peoples thoughts and feelings? How many of you are looking for heavy relationships instead of easy going ones etc. There are for sure some, but the majority wouldn't.
I have constructed quite a few scientific psychological tests myself, so I could probably write a 10 page article here about validity and reliability, about pretesting, about difficulties of information gathering etc. etc. but I will not do it because it is pointless, since most people enjoy doing those tests anyways like many of them enjoy reading horoscopes.
And still, I think those tests are good thing. Why? Not because they really tell you who you are, but because they bring you to the question and make you start thinking about it and eventually find your answers and your inner peace. And this is something we so often forget to do in our daily haste.