To get past a firewall and into a LAN,you need either a secret backdoor or a cooperative agent on the inside. A Jabber client on the LAN contacts a public Jabber server and wait for instructions trickling in as instant messages from its Internet buddies.

Armed with just a rescue CD and a Perl script, you can back up a client’s hard disk across the wire.

Testing complex web applications does not necessarily mean investing in expensive, proprietary tools such as Test Director or Silk Performer. Selenium is for free; it can remotely control any major browser, and it is programmable in Perl.

Spammers don’t just send email. They exploit discussion forums and blogs, posting pseudo-messages full of links to dupe search engines. A Perl script cleans up the mess.

Video files are ready for download, but your storage space is limited, and, if you're like most people, you may have a hard time letting go of past favorites. You need a higher authority to decide when it’s time to trim down your collection.

Perl hackers take to the hills with a navigation system that provides a graphical rendering of a hiking tour.

Webcams are useful for monitoring. Using CPAN modules and custom-made C code, Perl scripts can automatically adjust the exposure and fish the most interesting images out of a video camera’s data stream.

You can build a plugin in Perl to harness the power of the Nagios monitoring tool.

Lexers and parsers aren’t only for the long-bearded gurus. We’ll show you how you can build a parser for your own custom applications.

Linux lets tinkerers connect their hardware creations to computers. We’ll show you how you can use a simple Perl interface to check the temperature of your home or office while you’re away.