Explorations of Compositeness
  Some of the motivations for quark and lepton compositeness, and some problems associated with present schemes, are noted. One model is discussed in which quarks and leptons are taken as composites of spin-1/2 fermions $F$ with charges $\pm 1/2$ and spinless bosons $\bar S$ with charges 1/6 and -1/2. 
Jonathan L. Rosner