When I needed to go to High Hrothgar for the first time, I didn't feel like finding the path, so I just bought a horse. And flew to the Throne of the World (whatever it's called.) At like level 4. But then I fell off the mountain and died.
i alsways laughed when i broke the game doing that and horse just looks like it floating. and speaking of physics breaking i had a deathclaw in fallout 3 that kept leaping into the air nonstop when i tried to hit him XD
I once took this to far. I hopped on a mountain and never came back down, because of an invisable wall <.< There are still places in Skyrim no adventurer ever touched and survived to tell (because they had to reload their saves to come back down...)