If you use SuperCron for Drupal (who doesn’t?!) you can call the different invokes seperately. Very handy if you would like to check if there’s email via mailhandler every 10 minutes, without running the complete cronjob.

How? You will have to find the key named SUPERCRON_SAFETY_VARIABLE and this key can be found in the database table variables.

And then? You put in a cronjob for example like this http://example.com/supercron.php?safety=<your_found_key>&module=<the_module_you_want_to_invoke>

UPDATE: ok. that was too fast! the variable changes on every cron run, so this doesn’t work! I’ll post an update soon!