I've always loved those 'Transformer' cartoons. Well, it seems that researchers affiliated with the 'Information Sciences Institute' at the University of Southern California are very close to designing some real-life Transformers. For now they are called SuperBots and they can already do an amazing range of things. Here's a short characterization of a SuperBot:
Superbot consists of Lego-like but autonomous robotic modules that can reconfigure into different systems for different tasks. Examples of configurable systems include rolling tracks or wheels (for efficient travel), spiders or centipedes (for climbing), snakes (for burrowing in ground), long arms (for inspection and repair in space), and devices that can fly in micro-gravity environment.