Parser combinators for binary formats, in C. Yes, in C. What? Don't look at me like that.
Git-backed password manager
The Hammer standard library.
Revel module for Mozilla Persona
A consistent distributed data store.
Go client driver for doozerd, a consistent, distributed data store
A high productivity web framework for the Go language, modeled on the Play! web framework (similar to Rails).
HTTP Server Push module for Google Go