Custom links for category items in the legend?

Good evening Andy, I was wondering if it is possible to assign a custom beahviour to the category items in the legend.

Instead of creating a filter for the event category, I’d like to use a custom function to list events in the selected category. Of course this would require some custom programming, queires etc that I would perform personally, but this can be done only if the plugin exsposes itself to custom actions…. what do you think?