1) You mocked them... you tortured them... now they're developing the medicine that will save your sorry ass!
2) One who is academically superior to the normal population.
We don't like to rub it in... oh wait, yeah we do! PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS!!
Me: I bet you're regretting calling me a nerd now that you need that loan, right, bud?
Once-Popular Kid: Please, my tumor's growing!!!
Me: Hrmmmmm... Well, you should have considered this possibility when you decided that only nerds go to college.