Here's one solution: http://news.ycombinator.com/item?id=2461713 http://news.ycombinator.com/item?id=2461713 However given a file Mega would be able to tell wh

Here's one solution: http://news.ycombinator.com/item?id=2461713 http://news.ycombinator.com/item?id=2461713 However given a file Mega would be able to tell whether they stored that file, eliminating the plausible deniability they're aiming for.