  We review some of the possible observable effects (reionization, feedback on
galaxy formation, supernovae and metal enrichment) of the first collapsed,
luminous (Pop III) objects in the universe. We show that supernovae in these
objects should be considerably magnified by the intervening cosmological matter
distribution; the implications of this process are briefly discussed,
anticipating some of the results of Marri & Ferrara (1998).
