I was driving along when I heard a loud pop, followed by smoke coming
from my engine.  When I pulled over I saw that there was a perfectly
rectangular hole in my valve cover from which the engine was
hemmoraging oil:
http://putfile.com/pic.php?pic=10/30218590757.jpg&s=x11
Now the letter 'e' is missing from 'Porsche'.

Not wanting to get a tow, with an old can I found on the side of the
road I managed to make a patch to stem the bleeding so I could make it
to the nearest gas station.  Unfortunately the can could only take so
much heat before it started igniting oil on its own.  So right now I've
ditched the car in a residential area until the auto shops open
tommorow.

Does anyone have any idea what could have caused this?  I only paid 2k
for this car ('84 944).  Want to know if it's worth fixing. =/

Trevor