So I decided to fill the coolant reservoir up to the minimum mark and start the engine to see where my coolant was disappearing to. A little while later I noticed a pool of liquid under the car, and it seemed like engine coolant. It's definately not oil. Peering down behind the radiator, I could see some kind of "floor" underneath the engine. There was more liquid there, so it seems I have a leak somewhere down there, but maybe not at the top of the coolant reservoir, as I originally thought.
I also noticed, and this is where I need your expertise folks, behind the Traction Control System there's a small something, and this was also leaking small drops of clear liquid every 4-5 seconds. Could this be engine coolant as well, or is it something else? It's just outside the windshield.