$function() and $$variable
<p>What the heck is <code>$function();</code> and <code>$$variable</code> for? </p>

<p>Have never heard of these before, and searching on google doesn't give anything useful (possible that my keywords aren't perfect).</p>

<p>via <a href="http://stackoverflow.com/questions/4891301/top-bad-practices-in-php/4891422#4891422">Top bad practices in PHP</a></p>
