Well MIT has a solution for you install a Jet Engine the size of a Quarter in your Laptop that will actually run on Jet Fuel and in turn the micro engine will run a generator capable of producing enough power to run the laptop. Carry around a small bottle of fuel and you are all set.
Now here is the kicker the Laptop will cost you the same it does today but the micro jet engine will set you back several 100,000 dollars. [MIT]