Software
R packages for modeling variation in rates of continuous trait evolution:
Evolving rates
A novel approach to modeling continuous trait evolution that allows the rate of evolution itself to gradually ‘evolve’ over time and across lineages (pretty well-developed).
Continuous stochastic character mapping
A felixible framework for simulating evolutionary histories of continuous variables under all manner of Brownian Motion models (usable, not documented).
State-dependent character evolution
A new algorithm for fitting models of interdependent evolution among discrete and continuous traits (still a total work in progress–stay tuned).