Pathauto cookbook

My original motivation for pathauto was simply to get title keywords into URLs to help get Google's intentions. People are finding other uses for automatic aliasing by patterns, such as controlling block visibility or (implementation in progress) generating listing pages based on the criteria in the alias patterns. I'd like to put together a little cookbook that would:

1. Explain the various things pathauto is good for.
2. Help non-techie administrators understand how to use pathauto (pattern substitution may seem a simple concept to developers, but it's not necessarily obvious to someone who just wants to start a blog).
3. Provide some sample pattern setups for different kinds of sites.

So, what do you do with pathauto? How do you setup your aliases?

Thanks.