When I discovered Shift I wondered why it was named as it was. I started playing the game and I figured it was a pretty standard puzzle game with fairly ugly black and white graphics. When I got the fourth screen in the game I found the true beauty of this little time wasting gem and I found there was a very good reason it was called Shift.
When you finish paying the original Shift game you can move on to a slightly more complex version called appropriately, Shift2. If you want even more shift action and the ability to save your game progress and the ability to create your own levels you can play Shift3.
Enjoy!