How do mathematicians choose the problems they work on?  How do they make progress on problems?  How do mathematicians work together to solve problems?  I would like to address these questions of "mathematical discovery," describing some famous examples and an example from my own work.  The problem I am working on has its roots in the board game RISK, an old Putnam problem, the SET game, the Quarto game, and the Gitterpunktproblem (lattice point problem).  So far the problem is mostly open.