I had some connectivity issues at first, but my router is cooperating now. I invite you to check out CollabRL: the multiplayer dungeon! The concept is simple — you can move around, and you can drop letters for others to see. Updates to the map happen in real time.

The map started out as a complete void, but slowly the explorers left goodies and now it is pretty interesting

You can grab the bugfix version (and the freshly compiled Linux version!) at the entry page.

A screenshot of the initial area:

More screenshots after the break.