The svnmailer is a tool that is usually called by a subversion hook to submit commit notifications in various ways (at the moment: mail via SMTP or a pipe to a sendmail like program, news via NNTP, or CIA live tracker notification via XML-RPC). It is derived from the original mailer.py distributed with subversion, but should be much more consistent, more extensible, and have many more features.
RCSSmin is a CSS minifier. The implementation is based on the semantics of the YUI compressor, but aiming for speed instead of maximum compression so that it can be used at runtime rather than during a preprocessing step. rCSSmin does syntactical compression only (removing spaces, comments, and possibly semicolons). It does not provide semantic compression (like removing empty blocks, collapsing redundant properties etc). It does, however, support various CSS hacks (by keeping them working as intended).
Template Data Interface (TDI, /?ted?/) is a markup templating system written in Python with (optional but recommended) speedup code written in C. Unlike most templating systems, TDI does not invent its own language to provide functionality. Instead, you simply mark the nodes you want to manipulate within the template document. The template is parsed, and the marked nodes are presented to your Python code, where they can be modified in any way you want.