Good grief, I wouldn't know where to start I've been travelling, first hitch-hiking, then bicycle, since 1978. The first six years I was permanently on the road, and had just a sleeping bag and a sheet of plastic, and slept "anywhere".

One place that sticks out in my memory was a rainy autumn night hitch-hiking at a service place on the German Autobahn. I gave up, and the only place to "hide" was some bushes in the central dividing area of the autobahn.
In the morning there was a lot more traffic and it was a bit hairy crossing back!

Great thread idea OP
I'll search my memory for other weird places when I was with bicycle...

edit: If my memory is correct, that was the same night I was ID-checked at gunpoint by the Polizei. I think they understandably had a hard time telling the difference between hippies and RAF terrorists :/