I bought myself one of those Rayovac battery chargers, so I would stop having to buy damn batteries for my digital camera every time I left it hooked up to the computer and drained them...
$35 for the charger, $25 for eight extra batteries in addition to the two that came with it. Initial cost: $6 per battery. Better make these last, eh.
But I imagine the cost would be reduced even further if, say, everyone chipped in at work and got a communal battery charger, and a small pool of extra batteries so there'd always be some in the charge. If your batteries ever ran dead, you'd show up at work, take the fresh batteries out, put the dead batteries in, and you're set. Those batteries would be charged in an hour, ready for the next guy.
I wish I'd thought of that before I bought my own charger. Maybe I can be the company hero by bringing it to work.
But then, I don't suppose everyone else chews through batteries the way I do.
Indeed, perhaps I should have just bought some AC adapters.