Change the URL in the browser without loading the new page using JavaScript

Question

How would I have a JavaScript action that may have some effects on the current page but would also change the URL in the browser so if the user hits reload or bookmark, then

Answer 1

I would strongly suspect this is not possible, because it would be an incredible security problem if it were. For example, I could make a page which looked like a bank login page, and make the URL in the address bar look just like the real bank!

Perhaps if you explain why you want to do this, folks might be able to suggest alternative approaches...

[Edit in 2011: Since I wrote this answer in 2008, more info has come to light regarding an HTML5 technique that allows the URL to be modified as long as it is from the same origin]