GearBlocks is a game about creative building, interactive physics based machines, and gears - lots of gears.
GearBlocks pre-alpha demo - build 0.1.5567. This build has a basic sandbox game mode, a simple procedurally generated terrain, saved game support and a small selection of parts to build with. To install, unzip into any folder. See Readme.txt for keyboard and mouse controls.
As well as being able to save your constructions, the saved game support also provides a rudimentary way of sharing them with your friends. Saved games are stored as files in the SaveGames directory in the GearBlocksDemo folder (i.e. right next to the executable, you can create it if it doesn't already exist). You can load up someone else's saved game by copying their file into this directory.