Yep, the device like bac listed (or a homebrewed equivalent) plus that set of plugs sounds like it'll do the job.

I read one post in another thread about someone who had his N8** drained of its charge after being plugged into the device linked to above. Could he have just been guilty of leaving it plugged in for a long time with empty rechargables, or something like that? Or are these external battery packs really not so reliable?

And is the battery effected any more by a charge from an external battery pack than from the proper AC/DC charger? Basically, can it hurt the battery's lifespan in any way more than if you were to always use the charger?