When the first human colonists arrive on Mars, they could find a nice warm science lab and living quarters waiting for them, all built by thousands of tiny ant-size robots working and thinking collectively. European researchers are hard at work developing swarms of autonomous microbots. They can also do some other neat things aside from colonizing other planets, such as joining together to form larger robots, just like the Constructicons. Form Devastator!The robots are being developed as part of the European Union's I-SWARM program. At this point in their research, they have assembled groups of 100 robots (their official term for these groups seems to be posse, which seems hilarious for some reason) that can communicate with each other and team up to perform tasks too large for a single bot. In one example, a robot runs into an obstacle, and shortly thereafter a bunch of other robots show up to move it out of the way. The plan is to create robots that can reconfigure themselves based on the situation at hand, or even combine with other robots to form more complex machines. So far, they have tiny robots (pictured) that carry two kilobytes of RAM and move by vibration, and larger robots, called Jasmines, that roll around on little wheels. In addition to their Martian construction duties, the robots could be used as repair teams inside larger machines (like the Nanites on the Satellite of Love) or even medical robots that crawl around fixing things inside people. Throw in the fact that these robots will surely someday escape human control and form bizarre, hostile microbot societies, and I think it's safe to give this the H.G. Wells Award for Scientific Research Most Likely To Result In a Science Fiction Novel or Movie Coming True. Image by: I-SWARM. Robotic Ants Building Homes On Mars? [Science Daily]
There was a book called Recursion that had humans doing most of their construction using little robots like that, but they could self-replicate. You could drop one and it would be programmed like DNA to replicate and construct buildings or whole cities. It was just one of the book's interesting ideas.