A quick tip for those of you owning a Macbook or Macbook pro. If you have ever wondered what your battery life is at, a really nifty app called CoconutBattery (doesnt work with Snow Leopard) is your key to measuring the capacity of your laptop battery. Another app is BatteryHealth.
If you have your battery under warranty, or have AppleCare, you can go back to Apple if your capacity is severely damaged. According to Apple, a well-maintained battery should retain 80% capacity at 300 cycles. If its less than that you can ask Apple for a battery replacement.