I originally thought it was important to have a LED lamp that used AA or AAA alkaline batteries - because of their universal availability.
Until I saw the Barnes & Noble little lamp - which uses two 2032 cells (fairly commonly-available in the U.S.).
My two-AAA-cell lamp makes the Kobo a little top-heavy after reading a few chapters (Kobo-carpal-tunnel syndrome ... (grin)).
Photos of the B&N lamp are posted at ...
http://gallery.me.com/clintbradford#100032
Clint Bradford