Just what I needed for a book light.  I tend to wind down at night reading OLD books that I don't want to clip something onto and weaken the binding, and this one will clip onto my bed covers, and the flexible neck lets me just point it at my book like a little lamp.  While the blue casing lights up, it isn't enough to be annoying or distracting.  I've been through several books with it, and haven't had to replace the batteries yet either.