Originally Posted by jurjan

Just to answer myself here a tiny bit:
the eCharge is interesting, BUT:
as far as I can get it it's just an external battery, capable of charging devices that can be charged with their battery in the device itself.
now, those things are not bad, but that would mean that e.g. I would have to tether our D40 to it after the internal battery was empty (it cannot recharge batteries inside itself).