Copying Form Data To New Window

How could I use Javascript to copy form data in text boxes on one form to the text boxes in another form in a different browser window. For instance, if I have the following form in the main window:
<form name="form1">
<input name="your_name" type="text" size="15" value="John Doe" />
<input name="todays_date" type="text" size="15" value="8/12/2011" />
</form>

Here's the psudocode for the second form:
Upon clicking that link a second window opens containing the form:
<form name="form2">
<input name="full_name" type="text" size="15" />
<input name="todays_date" type="text" size="15" />
</form>

How could I use Javascript so that the click of a button will copy the contents of "your_name" and "todays_date" in form1 to the new window's "full_name" and "todays_date"in form2?