I know that the light-boxes produce a broad-spectrum bright light which is supposed to work, but my own experience has been that the daylight bulbs can have a significant effect on their own. I didn't mean to make out that they're the same, as I know they're not - simply to say that in my experience they do help. As yet I've never forked out the £100ish for a "proper" lightbox, but I have forked out the £6ish for a daylight bulb.