Symplectic Microgeometry I: Micromorphisms.

link: http://arxiv.org/abs/0905.3574
Abstract

We introduce the notion of symplectic microfolds and symplectic
micromorphisms between them. They form a monoidal category, which is a version
of the "category" of symplectic manifolds and canonical relations obtained by
localizing them around lagrangian submanifolds in the spirit of Milnor's
microbundles.