For those who are thinking of buying a laptop, some things to consider...

Battery life.  The battery life stated in the specifications, is not always correct.  It all depends on the brightness you have the screen set to, and if you have the wireless lan switched on.  It depends on other factors also, such as if your watching a DVD your machine would be using more processor power thus flattening the battery quicker than if you were listening to an mp3.  or if you are listening to a CD it would require a certain amount of power to spin the drive.  A good example of this is the Samsung P28, although a 4 hour battery life is quoted, the average is 2-3 hours whist surfing the net on full screen brightness.

If you want more battey life out of your machine then turn the brightness down, switch of (or disable) unwanted services such as the wireless lan if you are not on the internet, or have no router. And disable the LAN and PCMCIA card slot.  You can do this from the device manager.

Batteries don't like being left fully charged or empty, leave around 40-60% in them for a longer life.

Don't always use your laptop on the mains, it was not designed for this, if you must do this then unplug your battery, or cycle it.  I.e charge and discharge it.  If you don't use it, you loose it!