More of a curiosity than a technical question. I have a Dell Vostro 3460 laptop, and I just noticed it has two magnets embedded on both lower right and left corners near the USB ports and headphone jacks. They are strong enough to hold a metalic pen or a small keychain, and it's not an electromagnet, since it stays on when I turn the laptop off. The cover is aluminum, so it's not like it was magnetized by accident either.
That's really weird and I've never seen anything like that in other laptops. Is that a feature, a side-effect of some internal component, or something wrong with my laptop?