Wow, this list is very nice! I already use a few of these (Com's Torches, Conduit Magic, Ambient Town Sounds, etc), and now have a couple others to try AND a new entry for my List of Stealth Mods. Thanks for starting/maintaining this! Anyway, here are a few of the more gem-like mods I find myself using:
http://www.tesnexus.com/downloads/file.php?id=8927
Nice little addition to the weather system; I use it with Enhanced Weather
http://www.tesnexus.com/downloads/file.php?id=16533
For as simple as this is, I consider this to be one of my favorite visual mods; makes absolutely every daytime screeny look better AND the game itself benefits to boot
http://www.tesnexus.com/downloads/file.php?id=22795
New, nice clutter, how could you go wrong? Plus it's II implemented; booyah
http://www.tesnexus.com/downloads/file.php?id=4574
Somewhat self-explanatory
http://www.tesnexus.com/downloads/file.php?id=27825
A lovely retexture set if you don't mind occasionally being blinded by an urn
http://www.tesnexus.com/downloads/file.php?id=4429 and http://www.tesnexus.com/downloads/file.php?id=14596 update
Because I need three alcohol texture replacers
http://www.tesnexus.com/downloads/file.php?id=9276
Again, self-explanatory
http://www.tesnexus.com/downloads/file.php?id=4354
Because sparkly is better!
http://www.tesnexus.com/downloads/file.php?id=16704
Don't know if this counts as obscure, but I hear people looking for this kinda thing all the time, so clearly not everyone has it
Anyhoo, it lets you know what mod any item/spell/character/whatever is from, and tells you if containers are safe for storage.
Garak's Staff Replacer - http://planetelderscrolls.gamespy.com/View.php?view=OblivionMods.Detail&id=1909 - http://planetelderscrolls.gamespy.com/View.php?view=OblivionMods.Detail&id=2221 - http://planetelderscrolls.gamespy.com/View.php?view=OblivionMods.Detail&id=2425
I hated using staffs until I got these
http://www.tesnexus.com/downloads/file.php?id=2909 and http://www.tesnexus.com/downloads/file.php?id=27739
Add a dripping-wet shader to the player, NPC's, and enemies whenever they are or were recently in the water or in the rain. I actually recently stopped using this mod because if you're wearing something that already has a shader (enchanted armor, for instance), that shader will be replaced with the wet shader while you are wet. Still, nice addition, and great for screenies.
http://planetelderscrolls.gamespy.com/View.php?view=OblivionMods.Detail&id=2946
New wines (integrated into II)
http://www.tesnexus.com/downloads/file.php?id=7693
Nice looking clutter, implemented into the leveled lists AND II
http://www.tesnexus.com/downloads/file.php?id=22653
Gives you a reason to care about what you wear. I recently stopped using this because I felt it affected performance, but enjoyed the mod.
http://www.tesnexus.com/downloads/file.php?id=28012
Definitely a lost gem (148 downloads???), this adds gloves to match vanilla mage robes to the game, AND integrates them via script.
http://www.tesnexus.com/downloads/file.php?id=27527
Best looking book replacers, in my mind, and not nearly enough downloads.
http://www.tesnexus.com/downloads/file.php?id=7155
I only really use this mode because it adds stuff to II, BUT it is sorta cool in that it adds new clutter items and stuff
http://www.tesnexus.com/downloads/file.php?id=8711
Adds lightning SFX indoors
and finally, I'm going to plug myself here (I know, I know, I'm sorry)
http://www.tesnexus.com/downloads/file.php?id=25982
Adds two new suits (each) to the Golden Saint and Dark Seducer Armor/Helmet/Shield leveled lists and makes all Saint and Seducer armor playable
I have discovered in the course of typing this that I have a both clutter and texture replacer fetishes... hmmm...
Anyhoo, yeah, add what you like from this, and keep up the good work
CC