Being a huge Harry Potter nerd, I associate the name with Albus Dumbledore first and foremost. And I think that's a very good association; I love the character and his name. I would likely never use it just because I want it to stay associated with Dumbles, though.
While my first thought is (of course) Albus Dumbledore, whenever I read Harry Potter, this name always left me with the impression of a bulb--maybe an onion bulb.