Periscope's updated their Folio booklight case to fit the Kindle 2, which still houses a little memo pad, a pen, and a retractable light for covert reading.
At $US50 it's not cheap, but since Amazon charges $US30 for a book cover already, you're only really paying $US20 more to be able to write things and read on the toilet with the lights off (twin LEDs!). The downside is that you need to use three AAs to power the thing, and combined with the pad, the pen and the weight of the notebook, the whole contraption has multiplied the weight of the Kindle 2 to the point where it's heavier than a regular book.
I've been reading lots of books on the Kindle and something like this would be fairly useful if I wanted to do so in bed without angling myself toward the lamp, but the added weight may be an issue depending on which way I was propped up. [Periscope]