Oh, you mean like this third party application that controls the temp of Dell laptops?
http://www.diefer.de/i8kfan/index.html
I don't mind paying a premium to not have to lug a plastic suitcase around. Below is a picture of my roommates "inexpensive" 15" Dell notebook side-by-side to a 15" Apple notebook. Notice a slight difference in mass?
Its all relative. What is that 1" vs. 1.5"(1.25"?) If you get a faster system at the expense of half an inch for some that it worth is. Meh...whatever. If Apple made a more workstation class laptop at 1.25" I'd jump on it.