Transmeta's approach is a very interesting one - they can certainly win the battery life contest. But Centrino offers pretty decent performance with good battery life. The only problem is that the Centrino platform (as ExCyber pointed out, not just a CPU) will not come cheap. Unless battery life is really important, I'd consider a mobile P4/Athlon. Perhaps even a notebook with a desktop CPU, the only problem with those is that they typically chop the clock speed in half when running off the battery. At that point I'd consider a Desknote, possibly with a killer external battery.