Go Binding

Source Code

http://github.com/pebbe/zmq2
http://github.com/pebbe/zmq3
http://github.com/pebbe/zmq4

Very similar implementations, the first for version 2.1 and 2.2, the second for version 3.2.x, the third for version 4.0.1 and above.
An API that is idiomatic to typical Go usage. Godoc friendly.
Includes re-implementations of all examples in the Zguide (april 2013)
Includes higher-level functionality for the security model (zmq4 only, including examples) and a reactor type.

CZMQ bindings

https://github.com/zeromq/goczmq

goczmq is a golang wrapper around the CZMQ zeromq bindings.

Alternative Bindings (2.1.x, 2.2.x, with basic support for 3.x)

http://github.com/alecthomas/gozmq

gozmq is currently fully functional for , but does not support zero-copy (instead, []byte arrays are copied into C-allocated buffers).
This software is in maintanance mode.

Alternative Bindings (3.2.x only)

http://github.com/vaughan0/go-zmq

This implementation supports using Go channels for sending/receiving messages as well as the traditional Send/Receive methods. Note that go-zmq is not nearly as mature as alecthomas's bindings, and third-party contributions are welcome.

Old Incomplete Implementation

http://github.com/boggle/gozero Gozero is currently not functional. It is an early prototype which could really benefit from your effort in finishing it. See README for details.

Gozero is developed against a current version of zeromq 2 (2.0.6 as of now),

http://github.com/sustrik/zeromq2