When minecraft 1.7 released this morning I started to think of those new pistons. It appears that it can hold lava and water and let it flow when you pull the lever. And when those two mix you get cobblestone.
This building is a way of mining stone witout destroy your landscape. In the bleuprint the diamond is glass and the gold must be a piston.
here is the link:
http://minedraft.net/?id=4e0e224e37f7923a23000003
you need:
450 cobblestone
8 gravel
44 glass
3 stone stairs
4 pistons
2 levers
2 doors
26 redstone
2 water
2 lava/magma