Question: Bit of a strange question here i know.

but i wanted to know if some kind of standalone engine for javascript exists..

basically i want to test running of my javascript without having to load a web page...

Maybe it doesn't exist? Like some kind of ide where i can run commands directly without launching IE etc...

I have a great editor but it doesn't support that.. i still need to launch ie / firefxo

What i was thinking of some kind of standalone javascript engine existed that i could write my code here and make debugging a bit easier... and then copy to my webpage.

I know firebug exists but you can't specifically do what i am asking cna you?

Any ideas?

Answer: 
I have found out recently that if you have Visual Studio installed you can debug JScripts with it by invoking a script like `cscript test.js //X` which pops up the Just In Time debugger window.

Then you can step line by line through the script with all the benefits of a real debugger.
I had a similar question, that wasn't too promising: [Is there a Javascript IDE that has nothing to do with a browser?](https://stackoverflow.com/questions/993968/is-there-a-javascript-ide-that-has-nothing-to-do-with-a-browser)

I think the best answer there was Mozilla Rhino - although for your purposes, a [server-side javascript](http://en.wikipedia.org/wiki/Server-side_JavaScript)-related bundle may fit the bill. The engines they use tend to be either Rhino or Spidermonkey, with a few other random ones.