In the Triratna Buddhist Community we do a practice that we call Just Sitting. It's described as
Just Sitting is a space of non-action in which anything can emerge. Often the fruit of the previous practice only emerges when you stop ‘doing’ it. And Just Sitting is the non-doing space in which that may (or may not) happen. Just Sitting also allows assimilation of what has just been done, and provides the necessary counterpoise to activity and effort. Just Sitting is a matter of simply ‘being’ with whatever happens in awareness, without attaching to it or rejecting it.
Link to quote is here.
I've always wondered if this is something that we've just kind of invented or adapted or is it common to other Buddhist traditions? Is it the same as zazen practice perhaps?