I've been an owner of Apple shares for about 3 years now (bought in around $17). Even though I'm not an Apple user, you could see the writing on the wall with their innovative designs, their fanatical user base, it was only a matter of time they would design something that would be a commercial hit (iPod). Of course, you can't rely on one product to keep a company afloat (ahem, Iomega), but if they can parlay this into a profitable and successful line - which they have up until this point (Mini, Itunes) - they can probalby milk profits for quite a bit longer.
Not to mention, looking at Apple's balance sheet, statement of income, statement of retained earnings, and cash flow, they look very, very strong right now.