Algebraic Topology: There are several different notions of what it might mean for a space to be "even" in algebraic topology, all of which have useful, increasingly algebraic proerties. Mike Hll will begin by describing some classical work due to Wilson, focusing on what sorts of things happen when we have only even cells or homotopy groups, and then he will describe more recent work (all joint with Hopkins), where building on geometric intuition, we construct a version of this that works also when there is an action of a finite group.