What is this plant or flower? Does anyone know what sort of seed/bud this is? I have not seen it before and it's not ringing any bells.
That is an unripe seed pod of Nigella damascena, also known as love-in-a-mist.
It is a common garden annual, partly so because it is attractive through various stages, from bloom to seeding. Also, it has a tendency to self-seed, making it a relatively hassle-free ornamental. Seed pods are also dried for dried flower arrangements.
The most common colour for the flowers is blue, but cultivars with white, pink or lavender tones are also available.
The seeds of its cousin Nigella sativa are a common spice in Indian and Middle Eastern cuisine.