Been creating a scarcity world for a very difficult server. The map is almost entirely desert and desert variants. I tried to keep the map as interesting as possible with only deserts. It's challenging from a design standpoint because I am unable to use stone (it's a rare resource) and have to make wood extremely rare. I decided to make acacia wood drop nothing when broken so I could use them aesthetically. I still have to build some ruined houses to scatter around the world.
The main desert looks like this. It's tough to get large scale screenshots in vanilla minecraft.
There are some giant caves in the mountains here.
Inside a cave
Some other mountains
My take on the Mesa
A dirty desert biome
A sandy cave
A "rock quarry" styled biome with deposits of coal
This is a giant dune biome with some oasises in it. It's really large scale so hard to get a good screenie
There are patches of red desert with some rock spires in them
An example of some of the structures in the world
I generated a few random maps, copy/pasted chunks of them into the map, and then drew around them. This allows for the feeling of random gen and saves a lot of time drawing. I have been using GIMP to create the map which I highly recommend: http://www.gimp.org/