My absolute favorite feature from older Macbooks was the access panel on the bottom for swapping the battery and hard drive. I'm not sure what models have them; I have a standard Macbook from ~2008 that has it. You just press a lever and the panel comes right off, exposing the user-serviceable parts. You could swap the battery using no tools in about 10 seconds. Or you could swap the hard drive using a screwdriver in a few minutes.