There have been many sneak peaks at passive cooking cases with great cooling performance (mostly using heat pipes) over the last decade or so. Most of them have been discontinued, failed, or who knows? Calyos is the best I've heard about recently - and now seems they're winding down, or at least not fulfilling their kickstarter promises so far. Why do these not work? Is this just over-engineering for a problem not as significant? My main interest is low noise computing.