Napoleonic : Total War II is a total conversion of Rome: Total War v1.5 in Napoleonic Era, featuring a lof of new historic factions and units, playable in multiplayer and singleplayer. There is too a playable campaign submod.
The best mod ever made for Rome: Total War Game.
Excellent graphics, which goes in pair with great optimalisation (my PC can't run Diadochi without cracking, and NTW works just fine).
Great battles, fantastic balance.
Absolutely brilliant!