Oil Leak

Did a coolant flush today and in the process noticed a small oil leak that appears to be coming from around the front differential and the oil pan. It doesn't appear to be a very big deal; there was just a very small puddle that had formed on the engine plate. What's the most common thing that might cause a leak there? Anyone have a similar issue before?

my money is on oil filter housing gasket.

See http://forums.bimmerforums.com/forum....php?t=1070662

The first picture points you to where to check on from the top of the engine bay to verify.

Could be a PCV hose. I had a leak in a similar place and that's what it turned out to be.