[Unobtanium-inc]

My rule of thumb is any sought after Porsche that you hold for 5 years will probably be worth more. No, they are not straight investments, but you can't drive a mutual fund. Unlike a lot of hobby's that are complete money pits, the Porsche hobby does have an upside.
But it's important to remember my first line here, any sought after Porsche, so don't start filling your backyard with 924's and Boxsters just because they're cheap and then be pissed in five years when they still are.

---Adam