Blackout

A few years ago, Leadership decided that managers could not be trusted to stagger employee vacation requests during our "busy time," which happens at Thanksgiving and Christmas (debatable, but that's fodder for another post), so they imposed a Vacation Blackout.  However, clever folks (uh, me) schedule their holiday time off in July so it will be honored.  For others, the Blackout means you must find child care solutions, defer that trip to Grandma's or be absent at your best friend's holiday throwdown because you gotta work.  Blackouts are  a perfectly legal practice, but I'd like to point out that, in the world of Marvel Comics, there are two characters named Blackout.  They are both villains.
http://en.wikipedia.org/wiki/Blackout_(comics)