If like me you wasted a good portion of your life wandering the wastes blowing away mutants and enclave in the origional fallout games you might enjoy this. Its an idie project with some sort of agreement with blackisle/bethesda that has turned those first fallouts into a mmo. Its free to play and although it is a client its pretty light, afterall its just two 90s games mashed together.
Word of warning, it is rock hard. In the single player you were the chosen one, here youre just some nub with a gun and it shows.
You will die a lot , then you'l die some more and everytime you die you lose everything on you.
Other than a few safe cities there are no newbie zones, anyone can kill you anytime they stumble upon you if they so choose (they will).
Its very much in beta and is likely to remain so indefinately, but alot of the community help out with mapping/quest building and also to implement the 3d models from the cancelled van buren project. These models are also being suplemented with stuff made by players.
One more thing it is currently expecting server wipe in the next few months where everything is clearedto implement massive updates and even the playing field whilst ensuring everything is thoroughly tested by the players, chances are though if you just wade in you will have a screwed up build like me and welcome the wipe.
I realise i havent really sold it very well but its more a case of if you loved fallout youl probably love this if you didnt then you will probably get bored of being shot in the face/stolen from/suicide bombed very quickly.
Check it out at http://www.fonline2238.net/forum/
If youre having too much trouble give me a shout and il give you a hand.