The integral Chow ring of the stack of at most 1-nodal rational curves
  We give a presentation for the stack of rational curves with at most 1 node as the quotient by GL(3) of an open set in a 6-dimensional irreducible representation. We then use equivariant intersection theory to calculate the integral Chow ring of this stack. 
Dan Edidin and Damiano Fulghesu