Some seed

The tiny fruit fly (Drosophila bifurca) holds the record for the longest sperm. Researcher Scott
Pitnick of Bowling Green state university, Ohio, found that the fly produces sperm that are 60mm long -
about 20 times its own length. In
comparison, the human sperms are
just 50 thousandth of a millimetre.

To produce these sperm, the fly
has large testes wound up like a rope
that occupy most of the fly's body.
Adds Pitnick, "About half of their
adult life, about 2 weeks for males, is
spent in a non-reproductive condition. That time is taken up just
growing these damn testes."