Xapian is a search engine library, scalable to collections containing hundreds of millions of documents. It's written in C++ with bindings for Perl, Python, PHP, Java, Tcl, C#, Ruby, and Lua. It is a highly adaptable toolkit that allows developers to easily add advanced indexing and search facilities to their own applications. It supports the Probabilistic Information Retrieval model and also a rich set of boolean query operators. Omega is a Web search application built upon the Xapian library. It can index a Web server's document tree (including HTML, PDF, OpenOffice, MS Word/Excel/Powerpoint/Works, WordPerfect, RTF, PS, etc.), or data exported from arbitrary sources (e.g. SQL databases).
Puno is a PHP module (PHP5 and Linux/Unix only) that brings the OpenOffice.org UNO Programming API to the PHP userspace. You can use it to write scripts that create, modify, read, and save OpenOffice.org documents (Writer, Spreadsheet, and Drawing). You can export these documents in various formats, such as PDF or HTML.