I use the fabulous MacPorts system to get some of the software I need for my Mac laptop.
I am also interested in keeping this software up to date, for a variety of reasons, but just to know that I'm getting the latest security patches alone has me interested in regular updates.
I hate checking for outdated ports manually over and over again though, aren't computers supposed to do that?
So I wrote a script that will periodically check if I have outdated ports, and if there are any it will send me an email with a list of the outdated ones.
You can fetch the script port-checkupdate from my website - there are some comments in the script, and it's really tiny so it should be easy to work with.
You will likely also want the mailtest self-contained mailer my friend Marek Gilbert knocked together as well - the script expects to use it