I'm working to implement an idea I had for a MMO back in 2001 and never did anything about until now. It will be a fantasy RPG with a unique back story and game world, with familiar hack-n-slash gameplay, unique crafting system and encouraging dynamic player interaction.
A concept-testing TELNET version is in development. The code for this is hosted at https://launchpad.net/protomud.
These pictures are from the OpenSim based world test: