im working in the 15 artifact trophy ... so far I have sold all of them. any you really like to use?

Wabbajack its humorious and can be used to make followers properly level up their stats.
Sanguine's Rose, summons powerful daedra need I say more.
Azura's Star/Black Star: No question
Spellbreaker: If my character uses shields this one is hard to beat.

I never sell the artifacts they can go into my personal museum.

My character always carries Azura's Star (White) and almost always carries Spellbreaker. She only carries what she uses (except those quest items that can't be dropped).

Skeleton Key

Yep. It's not going back until I'm at 100 LP either. Very handy little thing.

Stole my answer. Most of the Daedric quests are fun but the artifacts aren't all that special. For example, a lot of people like the Dawnbreaker sword but it doesn't offer anything better than what one can make with a decent enchanting score. And with a 100 enchanting score you can make something that's far better (Undead flee + Fire Damage). You don't get the explosion effect but it's effects are 100% consistent. OTOH, if you don't enchant then there's nothing like Dawnbreaker.

But in terms of uniqueness, you can't make anything like the Wabbajack--although its practical usefulness is only due to a bug in the game.

Azura Star & Mehrune's Razer

I keep azura's (black) star as well ... and wabbajack for follow leveling. sold the shield, not a fan of using them

Ring of Namira
Spell Breaker
Sanguine Rose
Azura's Star (Black)

I use the Ring of Namira on my werewolf character for rp purposes, but it is extremely useful. Constant plus 50 stamina with a plus 50 hp with each feeding and 50% increased hp recovery.

Hircine's ring is my favorite, i like the unlimited transformations it gives you

I've used the Wabbajack to level followers, but I use the Masque of Clavicus Vile every time I buy/sell.

The Sanquine Rose probably looks the coolest and is useful if you like to conjure. It makes a pretty cool http://i1209.photobucket.com/albums/cc398/buckomccane/Skyrim/daed_arti_01.jpg at the very least.

I use Ebony Blade.

Sanguine Rose. My Buddy. I don't go near Valtheim without it.

spell breaker is the most usefull imo, closely followed by azura's star. And i always carry the rose...but i don't think i've ever used it

I collect 'em all, but no, I don't use any.
In Oblivion, I wore Namira's ring, used the Skeleton Key, and wielded Umbra (not an actual daedric artifact, of course, but what you choose instead of the Masque of Clavicus Vile). In Skyrim, I can craft way better items than any of them. Heck, even most standard daedric enchanted items are better, right? And having to give up the Skeleton Key is a total gyp. So (other than the Key), they all go into storage.

Spellbreaker and Sanguine Rose

I don't know what I would do without the Sanguine Rose. Thanks again, Sam! <3

I also use/have used...
...the Wabbajack, for levelling followers
...the Masque of Clavicus Vile while trading, as well as an Amulet of Zenithar, but then I became so rich it didn't matter
... the Mace of Molag Bal to fill soulgems in the beginning, but then that character focused on two-handed weapons, and now I just buy filled soulgems instead
...Amulet of Talos, to reduce the times between shouts.

Azura's Star. Never go anywhere without it (except jail ).

Marcurio uses both Sanguine Rose and Wabberjack. If I'm ever feeling lonely I grab Marcurio who casts a Dremora and I cast Lucien and we have a party with some Draugr.

I only really use the Black Star. But that one, I use excessively.

Sanguine Rose, definitely. It's just too much fun, both the quest and summoning Dremora Lords!
Mace of Molag Bal & Azura's Star make a nice pair. I always outgrow the mace eventually but still keep it handy to switch to when I'm low on filled gems.
Spelllbreaker - I find it useful well into mid-game, or a lot longer depending on my character.

Dawnbreaker seemed cool on the surface but I was a little startled by the effects. It looks really pretty on my rack, though.

I actually used the Ebony Mail for a time. And cussed through most of that time. Not a good choice for that character, a half melee / half stealth archer. "Cool, they can't see me! Oh crap, I can't really see them either."

Does Galdur Amulet count as an artifact? If so it is that one. I rarely ever use artifacts and that is the one I sometimes use.

If I am playing a female who uses light armor then I will use the Savior's Hide just because it looks so cool. I will use Dawn Breaker for undead slaying if I'm playing someone who uses one-handed swords.

That's about it. The rest I just mount on the wall or through in a chest.

Also, I carry Azura's Star which has a Grand Soul in it, but I've never 'used' it yet because I haven't run out of filled Grand Soul Gems.

...and Cicero's Clothes. I'm pretty rich, but I won't say it doesn't matter because all these people who say money is useless in this game might have to eat those words when we have to pay 1 Mil Septims for an airship pass to get to the first expansion area.

Azuras star mostly because it saves me lot of time and money.