If you are looking to "jazz" up the background on your Android device using Google's new Material Design concept, look no further than this "Ultimate Material Lollipop Collection" of wallpapers. While some of these are simply compiled collections of already existing Material Design wallpapers, many of them are unique creations.
There are 675 of them, so it should be pretty easy for you to find something that suits your tastes. They are hosted on the Google+ page of J. Amourette who is also the creator of many of them.
The above image is just one example. Here's a link to the collection: Ultimate Material Lollipop Collection