  The last few years have seen the proliferation of measures that quantify the
scientific output of researches. Yet, these measures focus on productivity,
thus fostering the "publish or perish" paradigm. This article proposes a
measure that aims at quantifying the impact of research de-emphasizing
productivity, thus providing scientists an alternative, conceivably fairer,
evaluation of their work. Emphasis is placed on the scientist rather than on
quantities that can grow unbounded. The measure, defined initially for
manuscripts, is then extended to researchers and institutions.
