Activity 1/ buy 1000 points

Activity 2/ Sign up to Alaska Airlines, move the miles via points.com to PC.

Activity 3 & 4/ Hertz or Amex MR

Activity 4/ If you can't have all of the above 4

Now I got an invite from Alaska Airlines to e-rewards. Just by signing up and filling out data about y'self, you get 5 (e-rewards) $. 20 (e-rewards) dollars can be converted to 1000 PC points and voilá there's another activity. I don't know how fast these "$" keep coming, though.
NB you have to say you're living in the US when signing up to e-rewards. Just give any valid US zip code.