It is ubiquitous: jokes, puns, banter, poetry, the constant reinvention of slang...

I think that we, as a civilization, don't really have the infrastructure (habit?) to talk about language i.e. look at it as technology, much less modify it. There's people creating artificial languages, which is really cool, but there's no obvious way to apply that in a mainstream way.

Then again, if someone were to start using English in a different way, it might catch on. He would just have to optimize his changes for acceptable backwards-compatibility. I guess the beauty about people as communicating devices is that they can adopt to changes in protocol, as opposed to some others (looking at you internet devices).

Edit: an artificial language is a bad term, there's no such thing, because it would imply that there's a natural language. It's just a new language, sometimes academic.