Nomad Planets

I point everyone to this neat article:<br />http://news.stanford.edu/news/2012/february/slac-nomad-planets-022312.h… /><br />This article points out that there might be 100,000 times more nomad planets than stars in the Milky Way.  A nomad planet is a planet that is not orbiting a star but off on it's own.  These can range from Pluto/asteroid size to just shy of enough mass to become a star (failed stars/large jovians).  I imagine that these are what make stable jump routes so hard to create.  But they also make a new plot device for mis-jumps given that mass is what helps pull a ship out of the void.  You mis-jump and find yourself not near a star but out in the black and have to search for the mass that pulled you out.  Hopefully you are not heading directly to it.  Also it has likely deflected your jump vector and now you have to realign to get pointed back to where you were going.  But where the heck are you?  Where are you pointed?<br /><br />Most of these nomads would be cold rocks of various sizes and boring, both financially and scientifically.  They are not in an opportune spot to exploit financially and scientifically there are dozens if not hundreds like them elsewhere and even in-system where it's safer to study.  However there could be a few that are unique.  Imagine a nomad world that is tectonically active enough that you can walk it's surface with out freezing yet cool enough that you don't have to walk on lava.  There could be an atmosphere with the right gasses available for breathing at a suitable pressure.  Likely some form of gas mask or scrubbers would be needed to clean out the toxic fumes from the volcanic activity providing the worlds heat.  The world would be dark too, all the time.  Only volcanic glows would be seen.<br /><br />We could think up dozens of these worlds drifting in the blank spots on the frontier map.  What do you think?