I was at a crappy corner Chinese restaurant in Frankfurt once. I think there were five tables max - four four-tops and one two-top. Three of the four-tops were taken. I was alone and sat at the remaining four-top, closest to the door.

About three minutes after I ordered, three guys came in and didn't have anywhere to sit. I offered to move to the free two-top, but they insisted I stay as they didn't want to inconvenience me. The only problem was that they had nowhere to sit. So they sat with me, taking the remaining three free seats at my table.

It was the most uncomfortable fifteen minutes I've spent in a long time. We spent about thirty seconds making awkward conversation and then proceeded to studiously ignore each other for the rest of the meal. Needless to say, I wolfed down my food and bolted ASAP.