Footer at bottom of window...always

Hi all,

Just found out about this and am having a good play...

One thing i am struggling with a bit is to make the footer bar always sit at the bottom of the browser window.

Obviously if the content is longer than the browser window then the footer will be right down the bottom of the content (using _frame for the content), but if the content _frame is shorter than the browser window the footer comes up to meet the content, leaving a massive space at the bottom of the site...

Is there a quick way to do this or is it a case of fiddling the css??

Many thanks in advance...

Nick