Have you seen the modern Astroturf? The 2009 version is very nice and can be seen at EPCOT. It feels really good to walk on and you can add a rubber under layer for play areas.

There is an interesting pro and con article at Sustainable Gardening Australia if you think this is appealing to you. In some Florida counties we have Energy from Waste plants where the synthetic turf product will be incinerated 10-25 years after installation rather than land filled which adds to the facts of this article.

For more inspiration check out  Felders New Lawn