A recent article published in Nature describes experiments that involve a special alloy of metal that is liquid at close to room temperatures. This alloy interacts with a surrounding fluid, usually water allowing it to propel itself. It is a huge feat, motion before has come from some form of external manipulations of magnetic fields, as in electric motors, or forced changes in pressure, as in hydraulics. This self moving metal can create motion on a much smaller scale leading to even smaller devices. Imagine a small camera that can zip through your bloodstream and sweep up any bad cholesterol lying around or guide a surgeon’s knife in a life saving procedure.
The Journal of Nature is one of the largest scientific journals in the world, many groundbreaking advances in science are published through it. While subscribing to the journal itself is not cost effective for most individuals they do offer an RSS feed that provides brief summaries of the articles published in their recent issues. Check it out here: http://www.nature.com/nature/newsfeeds.html