I'd have to say that, of all the artifacts, the Sanguine Rose is the best for me, because it's a unique looking staff with an awesome enchantment.

My least favorites would have to be the Saviour's Hide and Ebony Mail.

-Saviour's Hide because it looks like I have boobs, and I start to worry about knocking things over. Also, I already have the Poison Resist as a Bosmer and the Magicka Resist with the Lord Stone.

-Ebony Mail because the black smoke whenever an enemy is near screws up my archery. That, and it's Heavy Armor.

The only daedric artefact worth making some effort to get it is Dawnbreaker, Meridia's sword, in my opinion. A great weapon against any undead and there are lots of them in this game, plus Meridia seems to be the less evil amongst the Daedric lords.

I always love collecting these in TES games. My favourite of all is the 'Daedric Scourge'. It's a mace that can knock powerful Daedra back into Oblivion, I know there is a spell for that but in Morrowind I don't think there was so that mace was always useful.

As for Skyrim's artifacts, it would have to be... The Ebony Mail for it's effects probably, I'm a heavy-armor guy when I feel like it so it's not that bad.

I don't however like Namira's ring, just because I am not a cannibal and my character does not condone such acts in Skyrim, which is why I quickly take care of that creep in Markarth.

Favorite: Black Star - Unlimited soul gem that can capture the soul of any being is undoubtedly one of the most useful items in the game.

Least favorite: Skeleton Key - Useless.

I would have to say my favourite is either the Mace of Molag Bal or the Skeleton Key. Both were very useful to me early on when my stats were low/med.

My least favourite has to be the Ebony Mail. At first I had thought I contacted some awful illness but then figured out what it was. While the poison was nice it did inter fear with my vision so did not wear it for long.

Favorite: Ebony mail or Dawnbreaker, love the look and abilities for them. Also, Meridia is one of my favorite Daedric princes, so that is another plus of Dawnbreaker.

LEast favorite: Skull of corruption: lets see, awesome, not-squishy wizard (well, priest, but you get the idea), or a staff that barely does any real damage...hhhmmmmmm, which one should I choose..........

I have Dawnbreaker on my Khajiit, but I didn't feel like doing it on my Bosmer or Altmer.

favorite: none they are creation of abominations! But if i had to say, dawn-breaker.

Least favorite: Ring of namira

Necromancer Amulet is very useful too, but only on a mage so overall, not my favourite..

My two favorites would have to be...

-Ring of Hircine

-Dawnbreaker

My least favorites?

-Ebony Mail

-Saviors Hide

They're both completely useless...at least that's what I've found.

Favorite as in most practical? The Black Star
Favorite as in bad ass? Dawnbreaker
Last favorite? Volendrung as I don't play orcs or two handed warriors.

Ebony Blade. It's the personification of evil. I love it. I also like the Ebony Mail. It is VERY underrated in my eyes. It muffles the wearer! Let me repeat this for deaf ears. It's HEAVY ARMOUR, and it MUFFLES the wearer.

The combination of Ebony Blade, Ebony Mail and Illusion is devestating. I plan on doing this on my next Khajiit playthrough.

My favorite is Meridia's artifact, Dawnbreaker. That sword is awesome, although I think they should have made the unique daedric artifacts more powerful. It's kind of pathetic that I can smith a better sword than a legendary artifact people write books about. My least favorite is the skeleton key, since lockpicking is relatively easy in Skyrim, plus you don't get to even keep it.

I would agree that Lockpicking is MUCH easier in Skyrim than Oblivion. But the Skeleton Key isn't the true artifact, the Nightingale Blessings are.

These two in combination are bad ass and are two of my favorites.

But if I must pick one then....beh, I'm a rebel so I have two favorites.

The worst one imo is the ring of namira.

I like Mehrunes Razor, I always get a lucky roll.
I don't like the Skull or Corruption. Just not that useful to me.

But I haven't used or gotten all of them. So I can't say for sure.

Boobs?

Don't hate the hide if you're not man enough to rock it right: http://i739.photobucket.com/albums/xx34/lordtru/20121017_231608-1.jpg

It's hard to pick a fav as every character has their own that fits them but a least favorite is definitely the Rueful Axe if that counts as an artifact...the most beautifully disappointing battleaxe in game. Another is the Skeleton Key, totally useless as by the time I acquire it I have hundreds of lockpicks and lockpicking isn't that hard anyway.

I'm surprised several people have chosen Namiras Ring as their least fav, +50 stamina combined with the bonus from feeding is perfect for my Orc berserkers finger.

Dawnbreaker is easily my favorite. I also like the Ring of Hircine. Azura's Star would also be one of my favorites, if the thing actually had an infinite capacity rather than just being reusable.

Namira's Ring is probably my least favorite.

Hahaha.

Spellbreaker is useful, just hard as hell to start to get it.

For me it's cause guards comment on how your breath smells like death and most of my characters don't use it.

My bosmer though, they used it a lot.