RF Online. The only MMO I liked. But It's dead for a really long time.

Rumble fighter?

Rising Force
http://youtu.be/kmX5a5or-5c
http://youtu.be/lWpAtDhFvZY

A typical korean MMO, but with cyborgs and battle mecha suits/robots.

Arche Age currently.

oh hey! I play Archage! :D

World of Warcraft. It took over my life for years XD
Still fun to dip into now and then but I can't justify the cost anymore.

No other MMO I tried really grabbed me. Guild Wars 2 looks nice, story is interesting, world is fun to explore but I found the combat meh.
Final Fantasy 14 is pretty good actually, had a ton of fun playing that but again, can't justify the price really when I was playing it so little.

Yea I know alot of people that life got wasted by WOW XD

Mabinogi would be my favorite MMO right now, but I've played many others that I really liked, including:

Phantasy Star Online 2
Dungeon Fighter Online
Granado Espada
Wakfu
Dream of Mirror Online

and I plan to play the upcoming Tree of Savior when the international closed beta comes out.

So many i never seen XD

Archeage and WoW.
I've mainly been playing ArcheAge lately because of all the PvP and Sandbox elements. So much fun.

I've played so many..

Tera Online
Neverwinter
FlyFF back then...
and a lot more MMO's that I really don't remember xD

That scary XD

I'm playing Final Fantasy XIV right now ^_^

World of Warcraft. I've wasted years on that MMO, but the good times saw me through some tumultuous periods.

I never actually played online, but I liked Sega's "Phantasy Star Online" series.

I generally don't like MMOs, but I did really enjoy Elder Scrolls Online. It gets a lot of crap for being 'generic' or 'not Elder Scrolls enough,' but it had to do something right since I genuinely dislike most MMOs.