I picked up a battery charger for my spare N95 battery off eBay for the grand sum of £1. I had the problem of once I’d swapped out a dead battery from the N95 that it would remain dead until that night when it could be swapped back in and recharged. Now I have ready charged batteries all the time which is great.
I have one of these – I carry it everywhere…
It’s currently charging my spare battery from my laptop USB charger!