Mjoll, since essential (I'm on the xbox 360.)

I've heard the only other essential companion was that lizard guy, but I prefer Mjoll (never tried the lizard.)

Also, my dread thrall level 36 Thalmor soldier. With her and mjoll with me, I have fun. She CAN die (unlike Mjoll),
but is pretty dang tough with her default glass armor made legendary and double enchanted. I've only had her die
when she stood in a place where a swinging, spikey door thing kept slamming on her in a dungeon. The great thing is,
I just dread thrall again, after taking her stuff out of her corpse then putting it back in, and she is good to go.

Faralda. She's a mage, she's an Altmer, and she doesn't treat you like trash when you apply to the college.

Cicero. Funny comments guy.
Ho ho ho, hee hee hee...

Mjoll. Not into cavewomen, so not Aela.

Either Ghorbash or Borghakh.

After much experimenting, it's orc or nobody.

She's cool. I like the voice actress too. I wish I could marry her. Unfortunately, I get one Altmer female option... and it's Taerie of all people? Ugh.

I alternate between Jenassa and Marcurio, with long periods for each. If equipped well, they both sneak adequately, make reasonable decisions about ranged vs. melee, behave pretty much as I'd expect their class to do, and don't seem to get in the way as much as Lydia did. I like both of their comments, too, by and large. I haven't tried any of the others, but I may do so in a future playthrough with a different type of character.

Brelyna Maron, just because she's a mage, not a pawnbroker.

lydia died for me, do house carls respawn?

No. And the Jarl won't give you another one either.

Learn to take better care of your pets.

natural selection im afraid

I think Jenassa is at the top of my list. She's just a well designed character. Something about dark elf females is just cool. She makes a lot of relevant/contexual comments, but doesn't talk too much. And of course, Lani Manella.. she's one of the better actresses in the game, even if her lines are short.

Cicero cracks me up - plus he's a badass.

Erandur. None tougher in my playthrough.

I've recently made my Follower have a Daedric Greatsword with an attack of 286. + our 3 Dremora Lords... Now I seriously don't need to do anything.. They can prolly take down Alduin by themselves now >.>

There is one and only one....and her name is LYDIA!!!..and i would marry her for sure.....bethesda pls hear our cryes we want to marry lydia....... seriously????

Kharjo has been my favorite follower so far. I'm not sure why though, but he's a good tag-along buddy.

All around, it's a toss up between Farkas and Borghakh Steel-Heart. The orcs really kick ***. The Companions have the most fleshed-out stories, though, and Farkas is adorable.

Honorable mention for Belrand and Vorstag.

Jenassa because she was no muss no fuss, and remembered me in her will when I dragged her into a dwemer dungeon and she died saving my life (yes a "The Edge" ref). She was awesome I miss her!

This was after I dragged Brelyna into the dwemer dungeon and when she got very low on health I kept healing her (she actually said "thanks" or something)... until after a healing session her feet got stuck in cement and I was afraid to leave her there so I reloaded a save. Never used her again.

I was hoping Erandur would get some love. He is by and large my favorite. Nice personality, friendly, and completely kickass.

Utherd, she can take a lot of hits, can do a lot of damage, and can carry just about anything without being over encumbered, and you can get her fairly early in the game. Although I only used her on one playthrough because followers are so annoying when you are trying stealth.

For me its Janessa because she mimics very well. She conforms to whatever style I happen to be playing.

Belrand (is that the name of the merc from Winking Skeever?) because his ability to use the correct staff is phenomenal. I give him all the staves I receive and every so oftern recharge them.

Marcurio (or whatever the name... the mercmage in Riften) was so cocky I was sure he would be a flop. But it turns out he was a stud. It fact he was too good. I can't tell you the number of times I shot a dead guy who wasn't dead when I fired the arrow, but he was dead before the arrow arrived.

Oh... and I almost forgot... Erik the Slayer for sentimental reasons. He levels nicely and you get to kind of mold him into what you want him to be.

I've been with Lydia since I first had the opportunity to use her.

I've tried others but I just miss her "i am swwooorn to carry your burdens" remark.

I've got her up to level 50 using the wabajack trick so the only problem is killing enemies before she does. She tends to kill everything really fast now so I have to beat her to the kills.

She also has enchanted blades armor on so she's hard to kill.

She's saved my butt more then a few times in tough battles.

They even wrote a song for her:

http://www.youtube.com/watch?v=uVBBxptpSY8&feature=related

you can learn alot from lydia

I killed Lydia... I feel kinda bad...but whatever.
I'm trying to get Cicero as my compainion, because I can always use a good laugh.

...after the marriage, you will be living with him on a bench within the Bee and Barb (in Riften)...

epic failed.