Parkour could actually be possible for skyrim, since it already has barrel roll animations, better jumping realism, etc. It would take some time to make this, so I wouldn't expect for something like this to appear before summer, but a lot of work could do the trick. I have no knownledge about modding what so ever, but I do know that adding a command line to make jumps higher and longer in the .ini files and programming the game to do a barrel roll if the height and/or lenght of jump exceeds x number of meters could do already some tricks. Climbing though will be a pretty complicated configuration, since you actually have to add a whole lot of programming, animations and physics to the game, slowing down the performance too. Putting parkour aside and going back towards the original disscusion matter, there is a 1st person body mod currently in developpement, and it should be ready to be playable in a matter of two weeks max. It is right now still in beta though, and might screw up your game, I've warned you. Anyways, here is the link to the mod; http://www.skyrimnexus.com/downloads/file.php?id=6002