Dom XSLT - neutral interface allows programs to access,modify and create XML documents.
Exif - EXIF stands for Exchangeable Image File Format, and is a standard for storing interchange information in image files, especially those using JPEG compression.
Gettext - Tools to produce multi-lingual messages.
Pspell Module - It can either be used as a library or as an independent spell checker. Its main feature is that it does a much better job of coming up with possible suggestions than just about any other spell checker out there for the English language, including Ispell and Microsoft Word.
Sablot XSLT - Sablotron is an XML processor implementing XPath 1.0, XSLT 1.0 and DOM Level2. It also includes some other features such as XSLT debugger, SXP (access to external documents via callbacks) or EXSLT support.
XML RPC - It's a spec and a set of implementations that allow software running on disparate operating systems, running in different environments to make procedure calls over the Internet.