Holy forget.
I strayed from my settlement a couple hours ago to find a new location for a mine, seeing as how the current ones had been stripped bare of valuables.
I decided to go far north. I rounded a mountain and managed to find a neat, perfectly round crater with a lake inside. There was a nice cave, so I decided to set up camp there. Torches were placed throughout the mine and I planned to make a shaft in the lowest part of the cavern. I put wooden walls up on the entrances, and crafted doors to make things safer. I was satisfied with the setup, and climbed the edge of the nearby mountain to place a stone beacon (topped with an ever-burning brazier). I realized I was out of wood, so I decided to head back home to get more supplies.
I went quite a ways before realizing that this was not the path home. Rather, the opposite direction. I went backwards and landed back in some woods, and found more lakes. I couldn't understand it. I had went straight forward, then backward, but there were no signs of my activity to be seen. No torches pointing the way home, and no walled off caves marking my previous location.
I wandered around for an hour, being attacked by every monster in sight. After a while, I landed back in my starting location. I had gone in a circle. I decided to retrace my steps from there, when I realized that this was, in fact, my mine. It had reset completely. The paths I made, gone. The walls, gone. The sign marking "North Lake Mine," gone.
Eventually I found my way home, but that few hours of being lost, and contemplating Self Delete to find my way back left a bad taste in my mouth.
I really don't want to end up passing in and out of the Twilight Zone again. Notch needs to fix this.