  This paper proposes two phenomenological quintessence potentials with
parameters fitted to the presently observed ratio $\rat$ of smooth energy to
clustered mass and limits on the equation of state parameter $w_Q(a)=P/\rhoq$,
for which the quintessence potential is now slow- or fast-rolling. These two
potentials are intended to illustrate rather different quintessence
phenomenology since tracking and into the near future. Neither can be a
fundamental potential derivable from present-day string theory.
