Mailatt is a portable Unix/Linux script for sending mail with MIME attachments. The Content-Type and Content-Transfer-Encoding are guessed, but can be overruled with command line options. There is support for HTML mail and non-ASCII character sets.
picbulk sends images to Picasa or to email addresses specified. Images can be shrunk on the fly.
A library that implements Perl 5-style regular expressions.
A modern software IP load balancer.