Project Steve Guttenberg (PSG) is a PHP-driven diary/journal/blogging application that integrates seamlessly into an existing Web site. It provides many of the core features (including comments, archives, searching, and an RDF feed) and administrative controls (all Web-based) of other, larger systems, but doesn't use a database, is XHTML 1.0-compliant and its look can be completely customised via CSS. It can easily be scaled to host several journal sites with a single installation.
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