OK, so a bit of an update. I just got ahold of some of the Energizer "Accent" lanterns last night.

Doing the "standing in the bathroom with the door closed and light off" test, these don't put out tons of light. I think they'd be best used as a nightlight/find your way around the dark room light. You could read with them, basically sitting at the edge of your book, but it's a ghostly/diffused light.

A couple intersting things about these lanterns - they fit snugly into a stake that's about 8 inches long, so they can be sunk in a yard (they were designed as outdoor yard lights).
Also, they have two half-circle rings on top that you could use to hang them off a suspended string or hook/nail in a wall.

They're designed to run on a single D cell, but with sizer/adapters for batteries, you could use any smaller battery to run them (for a shorter runtime)
battery adapters
Also, folks on CPF have talked about creating their own adapters out of pipe from a home supply store. I plan to store these with a single lithium AA battery in them, so they can store ready to use, and I can replace them with D batteries at leisure/when necessary.

Dave