Possible to have many Drupal sites share one database table?

Hi,

I've written a module that downloads headlines from a particular news source and then displays them in a block. The module gets run every half hour by a cron job. Every half hour, it checks for new headlines and stores them in a database table.

I'm planning on having many Drupal sites, perhaps 100 or more, use this module. It'd be wasteful and inelegant to have 100 different sites download the same data every 1/2 hour and store the same data in 100 different places databases.

Is there a way for drupal sites to share some of data with another Drupal site? Something like this would also be great for sharing common usernames and passwords. That way, you could log into many sites with same user name and password.

I know the answer is probably "no, not possible" but I just thought I'd at least ask.