If you like computers but live in the physical world you need to check out Phidgets.  The development kit they provide allows you to easily create sensor and display interfaces for your PC.  They have a basic USB interface which plugs into sensors (force, light, motion, etc.) as well as USB interfaces for server motors, LED systems, LCD displays and (for you big brother types) RFIDs.

Now that you have all this cool USB hardware, you can create an computer control for it.  Phidgets are interfaced via their supplied VB APIs (other languages are rumored to be in the works).