My daughter, son and I use the Energizer Folding LED lights I picked up from my local Target for $6.99 each. Light is provided by two Nichia LEDs (I understand they're the brighter "2x" type) illuminating two translucent plastic tubes. Runs on 4 AAs and provides two brightness levels. It doesn't clip on to books like other dedicated booklights but the angle of the light tube section is adjustable with relation to the base.
I find that running it on the low level is more than sufficient for my nighttime reading. I haven't opened mine up to check yet, but I'm guessing it uses direct drive for the low mode (a limiting resistor?) as it doesn't exhibit any PWM flickering. It's advertised to last 200 hours on a set of batteries on the low level but I've haven't used it nearly that long to know. I've had it for about half a year and it seems pretty durable, so far.
My daughter and son use them for reading and illuminating their general vicinity on car trips. The light is low enough that it doesn't distract their "chauffeur" (mom and yours truly.)