JoelGodOfWar's Simple Coordinate Mod
Current version is "1.9_1.5.3b", please make sure you download that version, and not 1.8-0.2.
This is a mod which adds various utilities and enhancements to make your life easier. Designed with the moderate Minecrafter in mind. It adds your coordinates(Nether and Overworld, and can auto send them to chat.), a compass(NSEW), a clock(Day/Night), XP (Amount you currently have, and amount needed for next level.), Biome, Chunk Coordinates, and Potion Timers. It works in both single player and multiplayer servers.
This mod was specifically made for the DataCraft Survival Server, found at Dataless822.net, to help with linking nether portals, and then had other features added. This mod was designed to be compatible with the Rules on the DataCraft Survival Server, found at Dataless822.net, it does not do anything that can not be done in vanilla minecraft, just makes them easier.
I'm releasing this as open source. Make sure to check it out on GitHub. If you happen to use the code in any way make sure to send me a PM because I'd love to see what you make with it.