This battery - it's big. It's very very big. It's like, big. Okay, so that's the downside of this battery out of the way, let's concentrate on the upsides. This is a third-party battery that fits nicely on the back of an AA1, lifting the unit at a 10 degree angle. You can't see that from the Amazon picture but hopefully the picture I've added will be up soon and it shows the size of this battery. As for usage, it took 4 hours to charge from flat to full, and with my AA1 (XP, 1GB, 160GB HD) running with the screen on @ 70% brightness (and not switching off), HD not powering down & in use 50% of the time, CPU running at 50%, wlan on and in use, it lasted 6 hours. That's amazing. With the screen switching off after 5 mins, and HD powering down after 10, the CPU at rest & wlan on, it lasted just over 10 hours.