When I first bought my Alienware back in 2008 I had noticed that they incorporated the used of magnets in order to keep the lid on the laptop closed, rather than the tradition sliding clip. At first I was concerned with this fact and wondering why they would mix magnets with technology packed so close together. However, over time various items (such as numerous cell phones, external hard drives, and other things) have made prolonged contact to the area where the magnets are (below the keyboard). As unintentional as this was, nothing ever seemed to be affected by it and obviously they wouldn't put in a magnet powerful enough to do any real damage, especially if it makes direct contact with the screen. So I stopped being so concerned about it and payed less attention to what I put down there.
Last night I had to adjust some things around me, so I temporarily place my USB 2.5" portable drive on the area where the magnets are (again, certainly not the first, or the longest time doing this). After about 2 minutes I go to move it back and I heard this beeping noise....and the ever so daunting sound that all PC owns dread...the tic tic tic noise a hard drive makes when it goes bad. When I go to move the drive I noticed the magnet, for the first time ever, had actually attracted to the drive and actually gave some resistance when trying to take the drive off. At that point I knew....there was nothing left on the hard drive.
Fortunately I only lost about 8 hours of work on a Maya project, and some of the original files for a concept painting I had done (not the JPG though). Only true thing lost was some pictures I had saved.

So I warn anyone who has a computer that may use magnets to keep the screen closed, beware of what comes in contact with it. They are most certainly NOT harmless.

tl;dr penguins rants about alienware magnets ruining his hard drive. Don't assume these to not be powerful enough to do damage.

P.S. One positive thing about this, I now totally have a justified excuse to buy a bigger portable drive