PageRank Explained with Javascript.

This tool via williamcotton.com is great for understanding how PageRank works, and actually testing how PR flows. Plus, it’s rooted in the best SEO mentality out there: actually delivering high quality content (a.k.a. knowledge) to rank high on Google (since ultimately Google tweaks it’s algorithm to deliver the best results – which really aren’t the best now since they’re often manipulated by SEOs, but probably will be in the future as Google influences the behavior of SEOs to fall in line).