Ulmaria - The Lost Kingdom - A Free Ultima Online server which has extra features such as weapons and armor that evolve as well as a level system and townhouses you may purchase. The server also features an item enhancement system.
Furion-PK - A Free Ultima Online server that uses a completely custom set of armor and weapons. Custom NPC's with perfectly maintained drop rates ensure a great economy. Stay for the incredibly balanced PvP system. PvP is Fighter (Melee) based with suplemental buffs from magery. 700 Stat Cap (Usually 400str, 200dex, 100int) and 400 Skill Cap. Skillgain is fast so you don't need months to gain. Lastly, this server is built with a leveling system. Kill a monster and type ".sac" and target corpse to get experience. Brand new, just created, so everyones on the same level.
Here's a preview of some of the content:
Devil armor/npcs/weapons (devil deals damage more to angel) (passive adds more damage)
Angel armor/npcs/weapons (angel deals damage more to devil) (passive regenerates health)
Acid weapons/npcs/weapons (apply poison on hit, low damge)
Legendary armor (+25% all combat stats and newbied!)
Arcane armor (resists all elemental damage)
Grid armor (absorbs hits, can switch between melee/ranged, needs batteries to be worn until death)