Point Lookout had a great Lovecraft quest to it something that i sorely messed from New Vegas.

Lonesome Road was epic as hell, walking through the Divide and having the show down with Ulysses is one of my favorite moments in Fallout.

But I have to go with Old World Blues, the comedy was great and I loved talking to all the crazy scientists it gave me a great Portal vibe about the whole thing.

Operation Anchorage and Lonesome Road are probably my favorites, best/coolest rewards in the game. I would say old world blues but that damn stealth suite makes you into a medx crack addict.... mothership zeta is up there too. But so is broken Steel... that hellfire power armor was awesome.

I don't like Dead Money cause I always die at the end. And I never meet Elijah. Maybe this time I'll go with a guide to understand what the hell I'm doing wrong.

I voted Operation Anchorage, love the mountain setting and the camo versions of the various armors (Plus medic combat armor from Zeta). And that Winterized T51-b. God, it's beautiful. Best power armor in FO3.
Story was ok, it gives you the possibility to see a small glimps of what the war was like, but for some reasons each time I left the VR the outcasts there would turn aggressive and rape me..

My favorite was Point Lookout from Fallout 3. It just gave off a horror vibe and I just liked that feeling and I also liked the characters to like Desmond.

For my part, I loved Lonesome Road.

It's difficult, it's where the wasteland are still in nuclear war. The riot stuff is beautifull, the creatures and marked mens (Not sure if they are called like that in Vo, in french it's the "Hommes-stigmates") are more stronger than any enemies I encounter before.

If you say the corrects words, you can learn much about Ulysses and even you! The Dlc was hard and I liked it. And Rawr as the hell of a challenge.

Point Lookout or Lonesome Road, both were great and had a blast playing through them!

I like Dead Money because the atmosphere of tense, and using junks to make things the keep player from dying. Especially in hard cord mode, it's extremely difficult but the thrill and use everything you've got to keep you from any COD(cause of death); like dehydration, starvation and especial sleep deprivation; because outside of the casino, there are only few places can sleep. dehydration and starvation are not that hard to resolve, but sleep deprivation? This is really serious problem. And there's also a problem for medical supplies. But the most deadly element is the red cloud. Concentrated red cloud zones are not a problem. The worst thing is HP woud be drained constantly in this DLC.
This DLC always let me think of the movie "Saw" because of the atmosphere with. As for survival elements, let me think of MGS3.
Although the story is not that good, but at least it's the best story in all of the DLCs(well, OWB is quite interesting, too; but the story...)

to be honest ima have to go with dead money, i really enjoyed that dlc it was the first dlc that really had me scared, like i was playing a scary game for example like out last

yup really enjoyed that dlc and i recommend that dlc to everyone

I Would have to say Broken Steel from Fallout 3 because its a VERY patriotic DLC because you work with the BrotherHood Of Steel (My FAVORITE Fraction) and because you get to go into the Presidential Metro to get the Adams Air Force base and plus you get to see Liberty Prime but he gets blown to pieces and also you don't have to end the game it lets you explore more and its good for testing mods and it send the BHOS patrols around DC with water to give to the needy

Before I start my little rant let me say spoilers can and more than likely will ensue so if you've never played a fallout DLC I advise you keep scrolling.
My favorite Fallout DLC would more than likely Operation Anchorage. As the first Fallout 3 DLC not only does it stand out from the rest, but it has a completely different feel from any other DLC. You fight the Chinese in Alaska as a soldier with your bestie Benji and get some cook experiences and choices along the way such as leading your own squad and seeing part of an Old World war and if I am not mistaken part, of the "Great War" first hand.
Zeta was out of this world yes (pun intended) but did not give me overall joy or immersion, more like tedious gameplay in which I just wanted to beat it for the items I could obtain (General Chase's Overcoat, Captain's Sidearm, etc.).
Broken Steel on the other hand just feel like an expansion on the original game, given that's exactly what this DLC was aimed to do, it just didn't give me the feeling of a "true" DLC.
Point Lookout, Dead Money and The Pitt too me were all too similar. Each had a dark aura as well as story to them. "Oh steal a baby for a cure" "oh survive in a creepy swamp with swamp people" and finally "watch out for dog because he'll murder your face off". The stories were all different yes but to me the feeling to them was the same.
Honest hearts story derives from the Burned Man aka Joshua Graham which is from the main quest line if you take the time to talk to Ceaser's fun-loving minions. This was easily one of my top three DLCs because it brings an idea, not a good chunk of the game, but rather a lore friendly idea from the main quest-line and expands it ten fold. It also brings a tribalistic feel to the New Vegas world that does not involve dubious amounts of Jet or Psycho.
Old World Blues was simply... Strange. You talk to Brains including YOURS, fight huge robot scorpions and have a gun that literally barks at you. This DLC felt like a more comedic twist to Fallout NV. You do find where many of the wasteland creatures derive from and joe they came to be in this DLC, as well as become good friends with your good pal Muggy and murder all the toasters, regardless I don't even know how to coherently play this DLC without crying of pure laughter each time.
Last but certainly not least we have Lonesome Road. This was a close first for my favorite DLC. This DLC brings the story of the Currier Six full circle. Between the immersion from the new enemies, works spaces, companion, weapons, armor and etc. this DLC stands high above the rest. The only part I did not like and to this day will not make it my number one, was the fact that you can not see Ulysses' damn face.
There is also GRA that adds weapons and challenges. Although it's a good investment, I did not think it compared to any of these DLC.
If you got this far in my rant I say thank you and also suggest a pat on the back for having the attention span to get this far in my post! Hope you guys enjoyed the rant

Honestly i have to say Lonesome Road. It gave you a feel of there still is life, and people are trying to accept the fact that the Old World is not going to come back. Plus, the choice of either killing or siding with Ulysees was really cool. I just always killed him. My second would be Old World Blues. Muggy was just amazingly funny.

Like mentioned above, it has to be Dead money for me.
I love the limit of supplies and each play through I always find new surprises >.<
My 5th time playing and I just realized you can find a hunting shotgun in the villa *facepalm*

*sarcastic post*
Wait... Project Brasil is an offical DLC right ?

My favorite dlc must be Broken Steel - because I could continue to play F3 after that. In New Vegas I'd choose Dead Money - because it was the one thing that NV was missing - a casino heist! And the slight "horror" atmosphere really added to the gaming experience.

However - there is no worst DLC for me! Even Operation Anchorage was a great DLC for me - I really enjoyed the Pre-war Scenario of it all!

I always liked Point Lookout...it was like Fallout meets Redneck Rampage. The Creepers and Bruisers just reminded me so much of Leonard and Bubba from that game...and the atmosphere in the swamps was just down-right creepy. Lots of fun.

Cheers,

N~dles

Lonesome Road, I just like the way they represented the nuclear fallout all over again, I thought they did a better job than Fallout 3 with it. Seemed like a much more hostile environment that anything I saw in FO3.

Ulysses was also really cool.

Fallout 3: The Pitt - because of the deep backstory there and the characters where very interesting. I liked being able to choose the Slavers or the Slaves. The Weapons and Armor where especially cool as well.

Fallout New Vegas: Dead Money - The sheer hardness of playing on Hardcore mode with that DLC made it 50% more awesome. The Gold which was there to teach you Sometimes you just Need to Let Go was amazing. The Weapons and Armor were also pretty neat. And finally the Companions were just amazing and had great backstorys to them.

Point Lookout by far. Honest Hearts is a close second. Bethesda did an amazing job on PL, the atmosphere was incredible.

From Fallout 3 I like Point Lookout. It has great side quests, and the main quest of that DLC was a great back story. I like how they tied in the evil book from the Dunwhich building. The creep factor of it as well. Fun DLC

From New Vegas I like Honest Hearts. One thing I like is for a very short time you get to have a job as a Caravan guard. I wish they would add that in the next game as a way of having a odd job to earn some caps. But anyway I like meeting the burned man and deciding the fate of the tribes. The battle and the drug induced side quest. Just made things different and fun.

I'd have to go between Old World Blues and Honest Hearts. I loved how the evil mastermind of Mobius was a confused old man, but the story of Joshua Graham brings HH ahead, as well as it's native-american styled world.