Sounds like an interesting project to me ;) I'd definitely start with LWP to pull the forecast data from the website. Depending on how the site is set up, you'll probably want to use one of the html parsing modules, like HTML::Parser or HTML::TokeParser to extract what you want from the resulting html. CPAN has a plethora of email modules, but I'm not terribly familiar with any of them, so all I can suggest is to check them out and see which one fits your needs and your system. ;)

As for other projects, there have been numerous threads with suggestions, like Do your homework! or Exercises (I've seen more, but I'm too tired and lazy to dig them up right now ;} ). Grab one of those, or think of a small tool you'd like to have at your fingertips and dive in. Some projects that have taught me the most came about because of off-hand remarks people made to me that made me thing "I could do that in Perl!" Next thing you know, I've got blinkenlights and Perlmonks Age Stats. You could also surf through the CUFP, Code Catacombs, and Craft sections of this site to find scripts you could build onto/improve for your own use. The possibilities are limited only by your imagination.;)

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$rattusillegitimus = Eliza::PerlMonks::Robot::new()