Amusing neologism: the narwhale distribution.  i.e. the statistical distribution with a horn.

That’s taken from a lovely essay in “Small Things Considered” about how some viruses operate in two modes.  In the mode your probably familiar with they infect the cell, repurpose things to reproduce, and the blow up the cell to go in search of more prey.  But in another mode they are more like a parasite.  It seems that when in this second mode they can provide a benefit to the cell, i.e. a defense against the first mode.  Oh nature!