I've been using the Duracell 2650mAh rechargeable batteries in my Bluetooth Apple keyboard and they last a really long time. I work on my computer for 8 hours a day constantly typing, plus any recreational time later in the day for my own use (I work from home). With all of this usage, I have to change my batteries maybe 3-4 times a year at the absolute most (I never turn the keyboard off, though I think it does have some kind of sleep mode after it's not been used for a while). As for a charger, it's just a generic 4-battery AA/AAA charger I got on eBay a few years ago when I bought some older 2200mAh generic batteries. It works just fine, though it's not the quickest I've seen.
As for my mouse, I use the Logitech MX1000, which doesn't use replaceable batteries. It can go a little over a week on a single charge, but when I notice it drop to 1 green bar, I sit it in the recharge cradle overnight.
