a LOT of people are complaining about the HOT hard drive, buzzing ac adapter, and the flimsy screen that cracks sometimes. can you all verify this
I have used the Latitude D600 in person and here are my comments on those issues.
(1) Hard drive - the unit I used had a 5400RPM drive, and although it did make the left palmrest warm, I cannot recall it ever becoming unbearably hot, even after I had the drive working like crazy to install Windows XP Pro.
(2) Buzzing AC adapter - Early revision AC adapters made intolerable noise (my T40 had this problem as well, but a new adapter fixed it). I assume Dell has fixed the problem by now, but you might want to go to Dell's support boards and ask the folks there about it.
(3) Flimsy screen - The D600's LCD housing is composed of magnesium alloy (cool and metallic to the touch) and as far as I could tell it was not flimsy in any way.
These concerns in my view are relatively minor and miss the D600's biggest flaw - a completely craptactular keyboard. The keyboard on the unit I used rattled and flexed like crazy, and the keys had almost no travel or good feedback. The trackpad was somewhat worse than I expected, but not horrendous.
The D600 is not a terrible machine, but get a ThinkPad T4x series or R40 (budget) if you can. They're easier to type on, and have a nifty scroll key that you can use with the trackpoint.