Toy building system

1. A toy building system comprising a plurality of building elements including two or more function building elements each for performing a corresponding function, and one or more control building elements each for controlling one or more function building elements, each building element including at least one connector for electrically connecting the building element with another building element via a corresponding connector of the other building element, the connector including at least one control signal contact;

wherein each of the one or more control building elements includes a main output connector configured to output a control signal for controlling at least one function building element; and

wherein the two or more function building elements are interconnectable so as to form a sequence of interconnected function building elements, and

wherein each of the two or more function building elements includes an input connector for receiving a control signal from one of the one or more control building elements or from a preceding function building element of the sequence of interconnected function building elements, and

wherein an output connector is configured to forward the received control signal to a subsequent function building element of the sequence of interconnected function building elements different from the preceding function building element; and

wherein each of the two or more function building elements is configured to perform a function responsive to the received control signal, in addition to forwarding the received control signal.

2. A toy building system according to claim 1 , further comprising a power supply building element including an energy source for supplying electrical power and an output connector; and wherein the at least one connector of a building element further includes a power contact.

3. A toy building system according to claim 2 wherein the at least one output connector of a building element includes a power contact configured to provide output electrical power for supplying the electrical power to one or more building elements; and wherein the input connector of each building element includes a power contact configured to receive electrical power.

4. A toy building system according to claim 2 , wherein the power supply building element is further configured to output a control signal via the output connector of the power supply building element.

5. A toy building system according to claim 1 , wherein each of the two or more function building elements include a stackable connector element including the input and output connectors of the two or more function building elements.

6. A toy building system according to claim 5 , wherein the stackable connector element of each of the two or more function building elements is configured to receive a control signal from the input connector of the stackable connector element, and to feed the received control signal to each of the two or more function building elements and to the output connector of the stackable connector element so as to provide a direct control signal path from the input connector to the output connector.

7. A toy building system according to claim 5 , wherein each building element including a stackable connector element and a building element body includes an electrical circuit; and wherein the stackable connector element is electrically connected to the electrical circuit via an extension cable.

8. A toy building system according to claim 5 , further comprising a power supply building element including an energy source for supplying electrical power and an output connector; and wherein each stackable connector is configured to receive the electrical power from the input connector of the stackable connector and to feed the received electrical power to the output connector of the stackable connector element.

9. A toy building system according to claim 5 , wherein each stackable connector includes a first connecting side including the input connector of the stackable connector element, and a second connecting side opposite the first connecting side, the second connecting side including the output connector of the stackable connector element.

10. A toy building system according to claim 1 , wherein each of the one or more control building elements of at least a first subset of control building elements includes a stackable connector element including the main output connector of the control building element and an input connector; wherein the stackable connector element is configured to block any control signal output by an output connector connected to the input connector of the stackable control element from being directly fed to the main output connector of the stackable connector element.

11. A toy building system according to claim 10 , wherein each of the one or more control building elements of at least a second subset of control building elements includes a stackable connector element including an input connector and an output connector different from the main output connector; wherein the stackable connector element is configured to receive a control signal from the input connector of the stackable connector element and to feed the received control signal to the output connector of the stackable connector element so as to provide a control signal path from the input connector to the output connector.

12. A toy building system according to claim 11 , wherein the stackable connector element is configured to feed the received control signal to each of the one or more control building element.

13. A toy building system according to claim 1 , further including an extension element, the extension element comprising a stackable connector element, a further output connector, and an electrical extension element, the stackable connector element including an input connector and an output connector, the stackable connector element of the extension element being configured to receive a control signal from the input connector of the stackable connector element, and to feed the received control signal to the further output connector via the electrical extension element and to the output connector of the stackable connector element.

14. A toy building system according to claim 1 , wherein each of the one or more control building elements include a further input interface for receiving an external input; and wherein each of the one or more control building elements is configured to generate the output control signal responsive to the external input.

15. A toy building system according to claim 14 wherein the external input is selected from the group comprising mechanical forces, push, pull, rotation, human manipulation, touch, proximity of an object, electrical signals, radio frequency signals, optical signals, visible light signals, infrared signals, magnetic signals, temperature, humidity, radiation.

16. A toy building system according to claim 1 , wherein each building element includes coupling means for releasably interconnecting building elements.

17. A toy building system according to claim 16 , wherein each connector includes coupling means for releasably interconnecting building elements.

18. A toy building system according to claim 16 wherein the coupling means comprise protrusions and cavities configured to receive protrusions in a frictional engagement.

19. A toy building system according to claim 1 wherein the input connectors are connectable only to output connectors and output connectors are connectable only to input connectors.

20. A toy building system according to claim 1 , wherein the function is selected from the group comprising motion, generating an audible sound signal, generating an inaudible sound signal, generating an electrical signal, generating a visible light signal, generating an invisible light signal, generating a radio frequency signal.

21. A toy building system according to claim 1 , comprising a plurality of function building elements whose function devices are configured to perform different functions.