Cookies per domain?

A lot of sources say that there is only 20 cookies allowed per domain, but they are mostly old. Does this rule still exist? I created more than 20 cookies and it still works? What is the current max amount of cookies you can make now? When you reach the max, what happens when you create a new cookie? It erases your oldest cookie? Or maybe a random one?

Here is a cool little tool: http://krijnhoetmer.nl/stuff/javascript/maximum-cookies/

Firefox 3.0.3 seems to remember the most recent 50 cookies.

Same goes for IE7.

I didn't test Opera or Safari.

Oh so it depends on the browser, I see... That was a neat tool. Thanks.