DendroPy (Sukumaran and Holder) -- a Python library for phylogenetic scripting and pipelining, with support for reading/writing, simulation, processing, manipulation, and statistics of phylogenetic trees and characters in various formats.
Ginkgo (Sukumaran and Holder) -- forward-time spatially-explicit agent-based simulation of multi-gene diploid genealogies under dynamic selection regimes for use in phylogeographic studies or method assessment.
cPhyProb C-extension of Python for calculating likelihoods in the context of phylogenetic trees
Also see the phylogenetic web services hosted here