I drove my partner across town this morning. A couple of hours later I want to use the car again and find this underneath the left hand side:

At the time I wasn't sure if it was from my car or not, so I drove to Sainsbury's and checked when I came back to the car for leaks - none. Feeling good at this point.
Then I get home and notice something funny with the waterbottle:

So I let everything cool down and come back for a better look
The water bottle cap (the water bottle is almost full to the brim with this goo):

The oil filler cap:


The oil filler:

Head gasket failure?