Two low-budget and low-tech Paramount movies will be battling one another for top honors at the box office this weekend as Paranormal Activity 2 takes on Jackass 3D . Most box-office forecasters are predicting that Paranormal Activity 2 will emerge the winner with about $25-30 million, with Jackass 3D settling for about $20-25 million in its second week. ( Paranormal was not screened in advance for critics, but since the studio "sneaked" it in several cities Thursday night, some critics attended the movie with other paying customers and quickly filed their reviews afterwards.) The two films also face a challenge -- but not much of one -- from Clint Eastwood's Hereafter, starring Matt Damon, which opened in six theaters last weekend and is being given a full expansion this weekend. It's expected to earn $10-15 million.