Spherical parameterization and Remeshing, E. Praun, and H. Hoppe. Siggraph 03. They use a regular polyhedral as the domain and map the mesh to this regular polyhedron, minimizing a measure of conformality plus stretch.
Minimize inverse stretch, i.e. the difference between the min and max stretch. This measure doesn't work well for long, thin triangles, so they split those.
They use progressive meshes to do a coarse to fine parameterization.
They unfold the n-gon into n squares.