Installing Bioperl and the Ensembl API
Perl has established itself in a number of very specific niches, including being used extensivley for Bioinformatics applications.
Ensembl provide extensive open access DNA sequence data, which can be accessed via a Perl API.
The instructions for installing the API can be found here.
Note that it is not compatible with the latest release of BioPerl, and the instructions direct you to installing version 1.2.3.