Raid Addicts (Custom-Legit): Fully Custom w/optional Chinese text
www.raidaddicts.org (alot of custom files) Max. lvl 87
Jest 3 (Custom-Legit): Tuned to lower populations solo with 1 group raids. Random loot style
www.jestemulator.net (few zone model custom files) Max. lvl 70
PEQ~ The Grand Creation (Legit): www.projecteq.net best live like experience with the highest population. (no files) max. lvl 65
VallonZek/TallonZek (Legit-PVP): +- 10 level old world pvp
www.pwnedemu.com (few files spells mostly) Max. lvl 50
Edge (Custom-Legit): Tradeskill based armor/weapons with stat based character development. Really interesting if you want to try something new.
www.theedgeserver.com (no files) Max lvl 250?
Alarian Empire (Custom-Legit): Fully custom quest based progression. Tons of quests and custom items.
www.alarianempire.com (quite a few files) Max lvl 80
EZ Server (Custom-Legit): Easy 4x exp with custom loot drops
http://ez.makeforum.org/ (no files) Max. lvl 70
Storm Haven (Custom-Legit): Very nicely done custom zones with custom items.
http://stormhavenserver.com/ (Spell files) Max lvl 70 (75 via quests)
Zeb (Custom-Legit): Original custom content with thousands of customs items and hundreds of custom quests
www.zebserver.com (few zone model files) Max lvl 70
Freedom Server (Non-Legit): summon items GM runspeed
www.jestserver.com/forums
A work in progress (Non-Legit): summon items
www.andmetal.net
Scars of Amerous (Custom-Legit): Fast progression with many content updates
http://scarsofamerous.com/
There are dozens of other servers that aren't listed here. These are just a few of the more popular ones.