Three months ago, when I started this little project, I wasn't even sure what 'low-key' photography was, let alone how to achieve it. There is some good guidance on the internet regarding how to go about lighting your shot, so you create this dark, high-contrast look. Try here to begin with.
Yesterday, while shooting some products for a client, I took a few moments to adjust my lighting set-up, so I had a single bulb, rather than my softbox, at a distance from the object, to create some interesting shapes and shadows. This was the outcome. Now I'm just dying to try this look with portraits - I love the dramatic feel you can create.