Will do. I'd put links, but in this case that is hard. Most can be found from Planet Elderscrolls, which requires registering but it's worth it. Now that Morrowind is getting a bit old there are a lot of broken links around google, but perseverance prevails!
Morrowind:
-Magicka Regen: several variations around, this is a MUST-have, all other ES games have magicka regeneration by default, including Oblivion
-No-Glo: several variations again, this will make things look... less glowy when you get to the point where all your equipped items are enchanted
-Better Heads & Better Bodies: again a must have, check out some screenshots
-Companion Teleportation: useful when doing quests that involve escorting, and specially if you use a companion mod like the one listed later, with this the companions teleport with you if you use any of the normal teleportation spells yourself
-SkipTutorial: several variations, only useful for those who make three new characters a day
-Ashlander Tent: a very cool and useful mod which enables you to buy an ashlander yurt that you can carry around, place anywhere outside and store all your stuff in... nothing beats decorating your own crib with trophies! \o/
-Slave Companions: you can buy a (naked female if you so choose) slave or few that can do various chores for you, carry stuff, fight etc... they even level up, and you can set their equipment normally
-in addition to those I use various cool/hot/evil clothing and armor mods, the web is full of them~~
During the two days I could play Oblivion, I only installed one plugin. Forgot the name and can't check it here, but it reverses the effects of vampirism. Naturally only useful if you play a vampire, and if you don't like the way it currently works. Normally, you gain the most power/weaknesses, get a Nosferatu head and scare people away if you DON'T drink blood for a few days. Drinking blood reverts you back to almost human, and you can again talk to people and walk safely under the sun... well, safe from the sun at least
The mod reverses this, so that when you drink blood, you get the most power/weaknesses, but you look almost human (thus not scaring anyone) and are almost able to walk in sunlight (1 damage per second, you can take it long enough to get things done, and I like the adrenaline rush). This is similar to Anne Rice's vampirism, and doesn't really affect game balance (actually it's harder since you're never fully safe from the sun, unlike with the original vampirism).
From what I've seen in the forums, there are a lot of useful tweak mods in development and out already, gotta look into those asap.
Meh! I wanna play
Gotta hope the computer isn't bork when I get home the next time...
I know there were a few total conversion projects going on, no idea of the results though. But the Construction Set does allow you to change ALL content. Most of game mechanics is hard-coded, though can still be changed to some extent through scripting. I have no idea of what Chrono Trigger is like, so dunno about that 
