Another funny koinkidink: Ray just mentioned, under the desk post, that a light for the keyboard might be nice. And a reviewer of my new Mighty Bright lamps said that's one thing he's using it for. I don't need it, but his keyboard is on a keyboard shelf and badly lit in the evenings.
They are originally made for (and for some reason still only promoted for) use by musicians for their sheet music, but they have many uses. They are very small and very light (they hardly add weight to a Kindle or a paper book), they have a neutral light color, and since it's an LED lamp, it uses very little battery. You can twist it to any position you like, nice construction.
They won't, you know, compete with the sun, but I think they can be handy in a blackout, so I have bought three, and I keep one on my desk for the odd occasion when I have to sign a check in the evening or summin'.
The grip on the naked Kindle is not so dang secure, which is why I put soft tape around it. Didn't help much, but a little strip of velcro did. (I went looking for actual rubber tape, which surely must exist somewhere, but people went blank when I asked for it.)
I think it has just sufficient light to help with a book in a typical room, and to give the little extra. The one I link to above is not available in the UK, but it has two "super" LEDs, so perhaps it has more light. [Update: my mistake, they are on A-UK.]