What is leaking here?

Tonight I noticed a little puddle under the tip of the front cowling on my Connie:


When I sopped some of it up with a tissue, the fluid looked clear and had sort of an acrid/oily smell, unlike gasoline. I think that the fluid dripped down onto the cowling because it was clean in one spot on the left, and I could feel some of that same fluid in that spot, although not very much, like it had nearly evaporated.
What is leaking here?