Unfortunately it's a very "closed" system and it has a lot of annoying characteristics which led to the idea of replacing it by glueing some already existing, open applications together.
(btw: it's also got exploits: http://secunia.com/advisories/15421/)
first of all a list of features that Groove provides:
- Instant Messaging (with online status)
File container with locking
Separate workspaces (each workspace has own forum, members, ...)
- IM: IRC / Jabber
Calendar: Mozilla Calendar Project / phpBB Mod: Calendar lite/pro
File container: Subversion
Workspaces: IRC channels and separate forums
The challenges are:
- Centralized point for administering users (requires some sort of user-replication between Subversion, IM and Forum)
- Replication between clients/server
- Packing all that together so that even Windows-Users will be able to install/use it.
- Making it pass firewalls easily (Groove tunnels traffic through external servers over HTTP at port 80)
The server-side is clear:
phpBB & Calendar mod, Subversion (with Web-access for easy file browsing), IRC server, mySQL, Apache
The client is mostly browser-based, but the replication would require a local Apache/mySQL/phpBB installation. I think it would be possible to make a nice installer which puts everything in place.
The replication would be done on mySQL level (requires v5+)
hm.... Currently I'm still evaluating this, but I really think it's worth the effort. (Really: I HATE groove!)