uGui Skew Effect?

I have a background as both a 3D artist (models) and as a website designer.
In CSS, there is a style called Skew, which does exactly what it says on the tin, it skews things.

I have made a quick demo to show what I mean:

Is something like that black skewed square possible dynamically using a script, not an image?

Not currently, but it is coming in a future release and available in the beta:
https://bitbucket.org/Unity-Technologies/2ddemos/wiki/Alpha%20Release%202