[math-fun] Mechanical models of long tail distributions?

We've all seen those balls-and-pegs mechanical models which produce good approximations to binomial distributions (and hence Gaussian distributions). Are there any simple mechanical models for Zipf's Law? Power law? Pareto distribution? Log-normal distributions? In particular, if one were trying to produce a power law distribution, it would be nice if it somehow involved the equivalent of a log-log plot (where the distribution becomes linear).