Late Night Software Ltd's Affrus 1.0:

"Affrus 1.0 is an integrated Perl editing and debugging environment for Mac OS X. It wraps Perl in a standard, familiar, and intuitive user interface."

Tapping RSS with Shell Scripts by Dave Taylor -- Here's how to write a shell script that watches the news from Slashdot.org. After applying the code in this article by Dave Taylor, coauthor of Learning Unix for Mac OS X Panther, all you'll have to do is launch the Terminal to see the latest Slash headlines.

via hbwt - GNU Screen: an introduction and beginner's tutorial || kuro5hin.org

"Most modern Unix-based operating systems (e.g. Linux, MacOS X, and BSD) come with a little console-mode utility called GNU Screen. It's a powerful tool in the hands of the console warrior, a veritable Swiss Army knife of text-mode human-computer interaction.

This utility, despite its considerable usefulness, goes unused by a great many people. Why is this? Few people even know it's there, and those that do rarely understand the problem it solves. In this article, I will explain what screen does for you, and provide a simple set of instructions for accomplishing basic tasks using screen. My audience is those that are skilled with the command line but who have little or no experience with screen itself."...

I'm one of the target audience ;-)