Alrighty for those of you who want to get the mask out of Labyrinthian but do not want to start the College of Winterhold Questline, here's some screenshots/explaination on how to reach the exit which leads directly to the room where the Dragon Priest is contained.
http://zassyen.net/images/ScreenShot300.png
-When entering the area via Fast Travel the first place you want to go to is the exit of the area on the northern left side. You can't miss it because it'll have some stairs and an arch.
When you get to that, head for the ledge as seen in the screen shot and jump on it.
http://zassyen.net/images/ScreenShot301.png
From there jump to the next rock to your left.
http://zassyen.net/images/ScreenShot302.png
And from there jump to the rock in front of you.
http://zassyen.net/images/ScreenShot303.png
Now you want to jump up to the ledge on the same rock you are.
http://zassyen.net/images/ScreenShot304.png
Jump off that ledge and land on the rock below. You'll have to change your trajectory a bit to get to it. You're almost there.

http://zassyen.net/images/ScreenShot305.png
Next you're to jump to this platform.
http://zassyen.net/images/ScreenShot306.png
From that platform, you're to make a long jump to the platform to your left, you'll have to make adjustments to your trajectory on the way. And presto, all done.
Note: I do not know if the door to the exit is locked, like the entrance. I completed the CoW questline long time ago.