Moebius is a python/MySQL-based object server, doubling as a mud (or a mud doubling as an object server, it's not quite sure). It provides support for basic OO interactions, and for live scripting on-line via python. We've recently added some primitive inter-server and client/server RPC-type mechanisms. However, we're short on python coders that can either provide code for the world itself (the various mud commands and NPC actions), or delve a little deeper into the engine itself (which is full of horrible bytecodehacks and similar). Drop by mud.bofh.net.au port 5000 if you're interested - but mind your head as you do, we're still fairly heavily in alpha!
Just an update, for any who may be interested - we are still under very active development, but haven't released an actual version for quite some time now. That's because we've been relying on cvs from the home site, http://www.bofh.net.au/mud/
There should hopefully be another release made soonish, but in the meantime, if you're interested in the project, jump on the mailing list (referenced from that page, hit reload if it's broken), we'll be happy to help out with installations.
Just released version 0.2.1 - this installs cleanly, and runs. We're looking for people interested in building and coding - note, specifically a mix of the two, there's a lot of space for fixing non-engine-specific features and bugs at a builder level, if someone knows or is interested in learning python. Drop by mud.bofh.net.au port 5000 if you're interested.