title: what Javascript implementations for .net exist?
body: <p>This is a question with its own answer, probably destined for cw</p>
  
  <p>Firstly - what are the characteristics of a good JS implementation (in my view)</p>
  
  <ul>
  <li>complete. It must be able to handle all JS constructs. Good tests are
  to see if it can compile things like jquery, prototype, underscore
  etc (of course many of these wont execute since they need a DOM)</li>
  <li>stable. No crashes, or sometimes works, sometimes doesnt</li>
  <li>Fast</li>
  <li>Silverlight support</li>
  <li>Nicely embeddable. I want simple interface between the hosting
  environment and the JS and back again. It should Just Work</li>
  </ul>