Macbook freezing, running slowly, and making strange noises

Question

Hi. Just today my wife's MB froze while doing nothing more than playing music in iTunes. She had to leave so just closed the lid. When I opened the lid later, it came back from sleep eventually (playing the music), but was making an odd clicking noise. It sounded like it was coming from the upper right side under the keyboard. It didn't sound like the noises the optical drive usually makes, and there was no disc in it.
I left it charging, and when she came back to use it later, found that it was running really slow, taking forever to open applications (prolonged spinning pizza of death), and still making that strange noise. She restarted it twice, and the same thing occured after a reboot?
Any thoughts/suggestions? We have applecare, so we'll likely be giving them a call if it doesn't go away, but I like to check here first.

Answer 1

The same thing happened to my notebook last night, and I did some research. Apparently one of the reader arms in the harddrive separates from the drive and swings loose, digging gouges in the magnetic disk.
If it still boots, make sure you get all your un-backed-up information off of it before it crashes.
Mine is dead, and the only thing Apple can do is replace the drive.