DARPA continuing to look for methods of cleaning up space debris. A machine with a giant net capable of flinging things down into the South Pacific or further down into a degenerating orbit where the objects will break up are just some of the options being discussed. Of course space debris is a problem for a lot of our satellites currently in orbit, but it came up again at the 2010 Space Elevator Conference.
Along those same lines, NASA is looking for a tether 50% stronger than commercially available technologies. Three teams demonstrated at the 2010 elevator conference all employing different configurations of carbon nanotubes. Nobody passed the bar this year but I look forward to seeing the continued outcome of developing along these lines.