#3. Beat this, Tunguska!
Everyone knows an asteroid had something to do with the extinction of the dinosaurs (and that the Tunguska explosion above Siberia was caused by aliens), but the finding that a lesser planet-pummeling space rock might have wiped out the wooly mammoth in North America came as a surprise to Ken Tankersley, the co-author of the paper that suggests this was the case.
According to Physorg.com, "Ironically, Tankersley had gone into the field with [proponent of the theory] Dr. Allen West believing he might be able to disprove West's theory." (Additional coverage at the Montreal Gazette, United Press International and LiveScience.)
#4. Puncture kit for your brain
Polyethylene glycol can be found in everything from skin creams to laxatives, but injecting it into the bloodstream after trauma to prevent injury to the brain, as reported in the Journal of Biological Engineering, is a new one. (Coverage at Nature and The Financial Times.)
The horrific crash pictured at the start of this segment was widely reported.
Credit: Punctured tire image from David Hunter, molecular structure of polyethylene glycol via Wikipedia, image of a punctured tire under a creative commons license from Windell H. Oskay (www.evilmadscientist.com), and bicycle helmet image from Kevin Bryant.