Honestly, i personally prefer an ENB that doesn't go too overboard with the lighting enhancements. The only ENB i truly enjoy is Millenia's ENB. It is simple, adds great lighting, minimal DOF while still giving it a nice effect and it will not slow your system down. i get a solid 60 fps with little to no hiccups. for reference i run a GTX 780. I highly recommend the enb. Good luck!

My favorites are ENB of the Apocalypse, Midhrastic's and Cyberdyne. The latter 2 are outdated for the most part but they look amazing for sci-fi stuff.

A matter of taste, but I adore Ormr's Cobalt and Rust ENBs.

Here are some great ENB's to use have fun at it.

Spoiler:

Tesvixen wrote:

My favorites are ENB of the Apocalypse, Midhrastic's and Cyberdyne.  The latter 2 are outdated for the most part but they look amazing for sci-fi stuff.

I'm using Midhrastic's right now in my fallout 3 replay. I like the depressing, gloomy feel of it for the dc wasteland. However, I prefer something totally different for new vegas, any suggestions?

Overgrowth is my preferd one , depends on specs and what you want ( and what your gonna use it for)

Oh if you think you have a decent PC, this is the one I use - it's a very nice looking ENB!
http://www.nexusmods.com/newvegas/mods/58477/?

I like Midhrastic's enb using it in my ttw play through because oxide enb is a little to much for my eyes.

I recommend Hitman's 47 enb as it looks great and is a weather mod

Yea I settled on using hitman's enb for new vegas as well

Hmm.. Ghost enb. It's a very nice enb i think for low computers.  ^_^

Oxide ENB its a good enb and its my favorite!

This is old, but I think newer people will still look, so here is my two cents.
Take a look at ENBs that float your boat, and look at the settings, DOF, and etc, it's pretty easy to mix and match
elements of what you prefer from different presets.
(even some Skyrim ENBs)
Tweaking ENBs is something I enjoy doing, but if it's not your thing, then I'd look through tru3th's ENBs to get an idea of what you want or don't want for Fallout in particular.
There are many options out there, but it's all about performance and aesthetics.
In the end, it's what you prefer.
I know I have a vague answer, but it's the truth.
Good luck to those out there still making their own style.

It all depends on what the visual effects you prefer. I liked very coincided with ENB of the apocalypse and Ovegrowth ENB. Great ENB`s creating a unique atmosphere straight from the westerns movies.