Jedi Academy Plus is the most popular modification to Jedi Academy game. You can download it here
Most of the servers use it. It is a server side mod, which means players not having it can play on JA+ servers as well (though they may miss some animations and other features).
Among many other benefits it adds for example:
- Lots of new hilts (including Swords)
- New Admin commands and RCON commands
- Many new emotes
- Alternate Dimension
- Grappling Hook and Jetpack
- Player duel isolation
- Clan support fetures:
- Clan tag protection
- Clanpass - inner pasword for clan members
- Customizable admin levels
- New special moves
And much more.