I was playing my shaman, heading north through the Barrens towards Ashenvale. A gnome mage ran past me heading southwards, she was almost 10 levels above me so I decided not to tangle with her. Less than 5 minutes later two UD, a mage and a warrior, ran past saying something along the lines of "after her!" "kill kill", emboldened I turned and joined in their hunt. Thanks to ghost wolf it didn't take too long for me to catch up to her, she was determined not to be caught by her pursuers however and made good use of polymorph, frost nova and blink to evade me. I hunted her relentlessly using frost shock and earth bind totem to slow her down as best I could. Eventually just to the south of WC the other two caught up and we finally managed to kill her. 
  
You guys will probably think I'm a dick for pursuing and killing someone who obviously didn't want to fight or perhaps a coward because I only started following her once I had back up, but it was a lot of fun. Going on this massive chase halfway across the barrens was epic, it reminded my of LOTR when Aragorn, Legolas and Gimli are tracking the Uruk-hai across Rohan.