Yep, that was the problem....the hose had gotten knocked loose somehow. I found it, reconnected it, and the windshield washers work just fine now. The fit wasn't all that tight, so I may look into gluing it or something later - but I used the washer a few times and it stayed on, so I'll leave it alone for now.

I think I also located what must have been the pump for the headlight washers, it was on the other side of the tank near the outer body panel. Strangely enough, I didn't see a hose running up to it, or even a place where a hose could have gone - but the view was somewhat obscured and I didn't have a flashlight. It'* not that important though, so I'll mess with it at some other point. I thought I noticed just a little bit of the fluid on the ground, but that may have already been in the parking space when I pulled up. In any case, the fluid wasn't draining out like it had been before, so I'm happy.

Now, if I can just manage to install that O2 sensor I've ordered without destroying anything... :P

Consider yourself lucky. On my '93 SSEi, both windshield washer pumps have developed leaks over time and had to be replaced. One of the pumps leaked around the shaft seal, and the other pump leaked through the plastic body itself. And no, I don't add battery acid or anything else to the washer fluid tank...just regular ol' premixed windshield washer solution.