Laptops with Decent Battery Life?

Dave Robillard asks: "I've been looking at new laptops recently (hooray for disposable income) and I can't find a single one that has what I want: relatively 'slow' processor (I do not need a Ghz PIII in a laptop), networking, and most importantly, loong battery life. The real reason I want a laptop is for coding on the run. I don't need to play Quake @ 100fps. Are there any laptop manufacturers out there that machines like this?" Any laptops out there that have a battery lifetime that exceeds 2 or 3 hours of usable lifetime?