I needed to take apart a my precious Thinkpad today. (The poor thing is getting on in years, and I needed to swap out its CPU fan.) It struck me as I was taking it apart. (something I've done many times) I don't know of any other puter manufacturer that makes it this easy on you. This is a primary reason I love the Thinkpad. It's like the Jeep of computers. Simple, easy to service, uses basic, standard parts and screws.
In the pic above you can see what I see when I take it apart. All the screw holes have icons stamped into the case that describe what they are holding in (that's keyboard and palmrest icons there). The number next to each hole indicates the length of the screw as spelled out in the key (pictured top right). You don't need a manual, you don't need to google some hacker's blog to find out where you should insert a putty knife (*cough* apple), you just look at the back, pull out the right ones, and you're into the guts of your computer. You never need anything more than a small phillips screwdriver.
Now, If you think about this, it's in IBM's (now Lenovo's) interest to make it easy. The Thinkpad finds its way mostly into corporate environments. When someone has a basic problem with their puter in a huge corporation, it goes over to IT, where some monkey pulls off a keyboard and changes out some ram, or replaces an Ethernet card, etc. That IT monkey, (or his department) most likely has some say in who they purchase laptops from next year...
Yeah, your average laptop user doesn't give a crap. But a do it yourselfer does. So like the guy who buys an old Jeep because they are simple and easy to fix, hackers and geeks gravitate to puters like the Thinkpad, because they are well constructed, and easy to screw with or extend.
Now if only it could run OSX. : (