ufget mirrors the latest userfriendly cartoon to a local file. It includes options to create a html file with links, store the days cartoon to a date specific file/directory and more.
The latest version is 1.51.
If you want more cartoons than just User Friendly, you should look at Daily Strips.
It's really really easy.
To make the most of ufget you can choose to also install the Date::Format and Image::Size modules in the same way as the LWP::Simple module.
Simple:
./ufget localfile
For example:
./ufget ~/public_html/uf.gif
See the builtin documentation for the more advanced options like storing to a date specific directory, create a html file for your server side includes and so on.
ufget takes a few options. Run it without parameters to see the included documentation.