1. Simple templates system (header and footer works for me).
2. a no frills system that's easy on server resources.
3. SE friendly URL's for pages.
4. allows users to search by categories, tags, and keywords.

Right now, I'm thinking about hacking a WP template and use that. It won't be a blog, so I want a less bloggy template.

Recommendations for free WP templates for static sites welcome too!