Is there a useful purpose for <style type="text/javascript">?

Question

What is the use and purpose this , is it useful?

Answer 1

It's for "JSSS", or Javascript style sheets; see here for more info. It's nonstandard and never really caught on outside of Netscape's original proposal, which you can read here. I don't think most browsers today support this; I've certainly never seen a website that used it.