Oil on top of the engine!

[j.fro]

Not to scare the crap out of you, but power steering fluid is pretty flammable...
The PS reservoir has an o-ring that can fail, might look into that.
The oil cooler could also be the culprit, and that's also a couple of o-rings.
Good news is, either way the parts are not to expensive, and the fix is reasonably easy.