Modbus/RTU
Modbus/TCP
My company (greenHouse Gas and Electric) supports j2mod which also has support for Modbus/UDP (Modbus/TCP packets over UDP), but I don't personally use Modbus/UDP. I mention j2mod because j2mod is being used as the "base" for posting open source Arduino sketches that support Modbus/RTU and eventually Modbus/TCP and/or Modbus/UDP.
I'd like to do more with 1-wire, just haven't had the time.
I'm toying with creating new protocols, but there are intellectual property issues to resolve.