IBM wins hands-down in my book. I buy a laptop every other year (mainly as a write-off, but also to stay current). Of all the brands I've tried (and repaired), IBM is the best built laptop around. Yes, it is true that they are always a little behind the other guys in terms of capability, but it is because IBM carefully engineers and tests their products before releasing them. The result is true business-class machine that is often never seen in retail stores. Get one! Every IBM ThinkPad I've owned has lasted at least 2 years in daily, heavy service before I sold it to my friends, and when I sold it, it was still in perfect shape (except for keys worn shiny from so much use). The only other brand I would recommend for durability/reliability is Sony, though Sony tends to load tons of devices on their laptops that need lots of intricate driver updates. I spend far less time maintaining my IBM (and Apple) laptops than other brands.
. I have had very good experience with FOSA (basically no name, but they have been around for a while). They have both light and cool, as well as heavy and powerful laptops and their features tend to be something you cannot get in the name brand laptops (example - can have 3 hard drives, 16.1" display and a full size keyboard with number pad)