  The COSLAB effort has focussed on the formation of topological defects during
phase transitions. Yet there is another potentially interesting signature of
cosmological phase transitions, which also deserves study in the lab. This is
the generation of magnetic fields during phase transitions. In particular,
cosmological phase transitions that also lead to preferential production of
matter over antimatter (``baryogenesis''), are expected to produce helical
(left-handed) magnetic fields. The study of analogous processes in the lab can
yield important insight into the production of helical magnetic fields, and the
observation of such fields in the universe can be invaluable for both particle
physics and cosmology.
