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.
CTL is a cross-platform control dispatching tool that makes it easy to automate any kind of distributed systems management or application provisioning task. Rather than writing complex and error-prone scripts that over utilize "for loops", CTL handles the network dispatching for you and allows you to focus on the actual management tasks you need to accomplish. In addition to being a dispatching tool, CTL comes with pre-built cross-platform utilities so you don't have to script actions like file distribution or process and port checking. You can also write your own custom utilities and share them with others in your organization. Custom utilities are defined in XML, and your scripting can be done in multiple scripting languages (Perl, Python, etc.), *nix shell, Windows batch, and/or Ant.