The set can be assembled in a variety of ways. The photograph above represents one horizontal configuration. The thumbnail at left shows one vertical configuration in which the marble run can be built into a structure over 6 feet tall.
With hundreds of pieces, an included AC-powered motor, and no tools required this seems to me to be one of those toys (like Legos) that can be used, enjoyed, and rediscovered many, many times.
Here is a link to Chaos Tower available via Amazon.com and other toy stores.