On this topic, what is a good rule of thumb for when to charge the battery?
For example, I avoid "topping up" the battery in my laptop for small amounts, as I have been told from a few sources that its lifetime is affected by charge / discharge cycles. Does the same idea apply to the batteries used in the N800 and N810, or are we a bit safer just popping it in when convenient

The article is quite informative there, and it seems to suggest no need to worry, but I am not much of a battery person.

One thing is for certain: These batteries are much easier to come by than the insanely specific laptop ones.