Karel,
I am sorry I don't have one - it was just an idea...
The problem ist, there are a lot of different weatherstations whitch can be connected to a PC how would it be the best way to get the weather data to the core - would it be a way to generate a xml-File with the weater data and store it on the Core or has the data to be stroed in a database? I have seen some weather station software that stores data in a MySQL database. The biggest problem ist, that most weather stations are shipped withh Windows software - how could this stations be connected? Most of this weather stations can also store the weather data in a text-file - i think it would be possible to generate an xml-file and send it to the core using an cron job...
This software
http://www.weather-display.com/index.php supports a lot of weather stations...
Johannes