I paid $250 UDS earlier time this year and downloaded the project type from sun's site.
I have not yet finished the project ... If somebody has a SCJD, I believe he is a competent Java developer. Definitely, SCJD can help you a lot in job hunting. The issue is that most new Java programmers cannot pass the test. I am not kidding.
On the other hand, if you are a competent Java developer like fromZtoA and Marco, I don't think you need such a certificate. For me, I don't need any certificates. In some sense, I regret downloading that prototype project----it is not easy to earn $250 USD.
At present, I don't have much motivation to finish this test. (spending a lot of time and $150 USD more!).