  We discuss the ``soft-ratcheting'' algorithm which generates targeted
stochastic trajectories in molecular systems with scores corresponding to their
probabilities. The procedure, which requires no initial pathway guess, is
capable of rapidly determining multiple pathways between known states.
Monotonic progress toward the target state is not required. The soft-ratcheting
algorithm is applied to an all-atom model of alanine dipeptide, whose unbiased
trajectories are assumed to follow overdamped Langevin dynamics. All possible
pathways on the two-dimensional dihedral surface are determined. The associated
probability scores, though not optimally distributed at present, may provide a
mechanism for estimating reaction rates.
