A set of Holographic skins for all the normal UT2004 player models, including Human and Skaarj skeletons as well as the ECE Megapack characters, Evil Engine's Battle Droid, Roadkill's Cylon, and Slyrr's Junkyard Mech, Bender, and Deinonychus (Raptor) models. More than 100 characters total, yet it is a small download (7 mb.) The Battle Droid model is included in the pack, but you'll need to have the other custom models installed to use their respective holograms. You can find download links for those characters at the above link as well.
Since this video is one of the top results when you Google "How to install UT2004 skins" I made a skin / model installation video: