I know this isn't specific to my computer since it happens on both my laptops and my work computer and on all browsers (IE, firefox, chrome)
but when i go to bimmerpost or e90post.com and it loads the main page if i put over my cursor over the "forums" drop down on top before the page is fully loaded the drop down appears for a second but then disappear even after the page is fully loaded when you put your mouse over the forums button the drop down is not there but when you move your mouse AWAY it for some reason shows up.
the only way to get the drop down to work again is to refresh the page and fully let the page load before you try to get to the drop down.