That moment when someone markets their Xen-ified Linux-based operating system as secure: https://lwn.net/Articles/727425/

Folks, adding a hypervisor doesn't increase security--it does the opposite.

@lattera not exactly. hypervisors can increase overall security by containment of applications. the PS3's security model is a good example of this (except for the part where sony signed everything with the same nonce this making the whole thing pointless)
@lattera this is of course not to mean that qubes itself is any good, mind. i consider that more to be proof of concept. X11 to tie it all together for example means it will never be secure