Architect is a fun puzzle game that can help you develop your spatial skills. Grab pieces as they fall and fit them together to form a solid wall that climbs in to space.
Move any piece at any time to any position (even under other pieces). If things get out of control you can pause and reorganize your pieces.
Be sure to fill in the bottom row completely in order to climb higher and higher.
If you're curious, you can read more about the thought process that went in to building Architect on my blog.