Integrate Lightning (Tunderbird AddOn) into Yosemite's Notification Center I currently went from Mac OS X 10.6.8 Snow Leopard to 10.10.2 Yosemite. I am kind of impressed of the "new" Notification Center" and asking myself if there is any way to integrate Thunderbird's Lightning Calendars and Tasks into this.

Incoming mails are integrated like a charm. However, my calendars aren't.

I could use Apple's Mail and Calendar Apps for sure, but I'd rather use Thunderbird for seamless integration in my Linux-Windows-Mac-based Workflow.
This has probably crossed your mind already, but you could sync all your Lightning calendars with the native Calendar app too (and just keep them unchecked in Calendar if you don't want those events shown in that app). That should take care of notifications, although you wouldn't be able to interact with them without launching Calendar.