My boss has had a Titainium Powerbook G4 for a couple of years without any problems. This was until a couple of weeks ago when he dropped his bag containing his Powerbook from about 4ft onto concrete (it was just a normal cloth bag so no real added protection). It busted the corner and put a small 2cm stress line on the screen, but it still worked. A few days ago when getting out of is car he forgot to zip up his bag and the Powerbook fell out from about 4ft again and landed onto concrete on the opposite corner to before.....Noooooooooo!!!!! (you could actually feel the vibration through the concrete). Its case is now bent and dented on both corners and the lid is scratched, but after all that it still works as good as ever. Even though it still works you can't help but feel a little sick when a computer hits the pavement.
I've managed to whack my little macbook a few times on metal poles n stuff, but never really dropped it. It's come close though. Apple make their computers quite strong, and even Macbooks/iBooks have motion sensors to prevent the HDD from dying on impact.
i've always heard good things about apple laptops and their durability. the metal casing of the pro series may get denty quickly, but they just keep going
I dropped my Dell XPS M1210 recently (cloth bag, no padding - slipped when I was trying to get the bag on my back). A small chip off the plastic casing right above the modem port. No other problems and everything works.
Lucky. The worst that has happened to my macbook is the cat jumping onto it and myself dropping a glass on top of it still works though... honest