What are people's favourite pre-WOW MMOs that are still worth playing today?

I long for the days of yore, but I never really got into MMOs until WOW and I've always been jealous heating the stories of people playing MMOs prior.

At some point in the future I'm going to be making an XP era PC build where I plan to play some older games from my childhood as well and any MMOs from that era that I missed out on

Also going to try and get properly into FFXI at some point too but I'm wanting to hear other suggestions too.

I've tried everquest but the way they center the character in the 3rd person view starts to mess with my motion sickness a bit feeling like I have to look at the ground a lot more than I'd normally prefer.