  We describe a simple machinery which translates results on algebraic sums of
sets of reals into the corresponding results on their cartesian product. Some
consequences are:
  1. The product of a meager/null-additive set and a strong measure
zero/strongly meager set in the Cantor space has strong measure zero/is
strongly meager, respectively.
  2. Using Scheepers' notation for selection principles:
Sfin(Omega,Omega^gp)\cap S1(O,O)=S1(Omega,Omega^gp), and Borel's Conjecture for
S1(Omega,Omega) (or just S1(Omega,Omega^gp)) implies Borel's Conjecture.
  These results extend results of Scheepers and Miller, respectively.
