Pike's recent post about her UI just reminded me that I was about to do one of those eventually. I'm one of those who will spend hours tinkering with things like eePanels to get just the right look, so I take pride in showing off screenshots of them, usually.
And yes, I love the look of minimalistic UIs. I try to keep things as simple as possible, but at the same time trying to have utility and just the right amount of information avaliable on screen.
I've been running that UI (and various iterations of it...) for several months now. It started out largely inspired by Rayne's Burnt Black Cherry Lite in BC, and over the months I've changed little things about it but managed to have it retain the same general feel.
Here's a little "progress montage".
Anyway, here's a quick and comprehensive addon list.
Pitbull, the one UnitFrame mod to rule them all. When I first started adding addons, of course XPerl was the first one I went to for unitframes. But after looking at a few shiny minimalistic ones on various sites, I was drawn to Pitbull. It may not be as easy to configure as XPerl out-of-the-box, but it has a ton of features and configurations. You could literally spend hours figuring out what does what. And when it comes down to looks, it does so very efficiently.
MikScrollingBattleText, or MSBT. I was initially using SCT, until patch 3.0 hit and suddenly my screen was flooded with a floating wall of green healing text, thanks to the new Bloodthirsty pet talent. Our GM at the time was also talking about MSBT, so I decided to give it a go, and haven't looked back since. It is much more customisable than SCT, especially the size of the text columns, which was my problem with SCT. All in all, a very useful mod.
eePanels, the mod that lets me put that delicious 1px white border on my unitframes. I've been told to update to KGPanels, and I did try it once, but it had too many settings and I wasn't in the mood at the time. :P I may go back and give it a go, but for the moment eePanels is the one for me. If you're interested in trying out making some art with eePanels, there's a brilliant tutorial on omgphatloots.
SL Data Text, text mod that shows various stats. I've been seeing UI screenshots that had durability, gold, fps, etc. in text along the bottom and was wondering for ages what it was before I finally stumbled across a post that listed it. It's really handy in that you can put whatever data you want, wherever you want it. I can't have a UI without this mod.
As for the others, well, they're pretty standard really.
Dominos for actionbars
Recount, Omen and DBM
Chinchilla for minimap
Bison for buffs/debuffs
Prat for chatlog
Quartz casting bar
Aloft for nameplate modification
oRA2 for maintank targets
You'll be able to find all these mods over at WoWInterface.
I'll post one of my druid tomorrow, since she uses a completely different UI.