Well it didn't happen by accident, since I did it on purpose, but after Odaviing took me to Skuldafn (SP?) I discovered that by messing around a little I can jump up the mountains surrounding you, and now I'm outside the little bowl that is Skuldafn and the world outside has like nothing rendered except mountains and stuff and ground missing. Just thought it was pretty cool. I'm on console btw so I didn't use any PC trick.

Interesting

You should take a picture and show it. I would like to see how Skyrim looks like from Skuldafn.

I should take a picture of my TV screen or something. There are some interesting things. I was running through this shallow water towards what looks like a tower or something far in the distance, or some land that had a weird rectangular shape. A dragon was gliding over the water. At first I thought it was just where Odaviing actually took off to and I thought it was him, but then it attacked me. So I used Dragon Rend, and the weird thing was, it didn't land, it took off far off in the distance towards Skuldafn, and landed in there I think. I think the dragon is pre-coded to go there or something. Still cool stuff though. Funny they didn't put the invisible wall, "You cannot go this way" up the mountains around Skuldafn. I guess they didn't think there was ways for the player to jump up the mountains.