whack-a-mole

n. [from the carnival game which involves quickly and repeatedly hitting the
heads of mechanical moles with a mallet as they pop up from their holes.] 1.
The practice of repeatedly causing spammers' throwaway accounts and drop
boxes to be terminated. 2. After sense 1 became established in the mid-1990s
the term passed into more generalized use, and now is commonly found in such
combinations as whack-a-mole windows ; the obnoxious pop-up advertisement
windows spawned in flocks when you surf to sites like Angelfire or Lycos.