http://en.wikipedia.org/wiki/Millennium_Development_Goals#Pr...
The problem, to me, is more of a logistics problem, because once you get more than ~100 people in an organization, you start losing the immediate connection with them, which means you care less about their well being, because you don't know them. The issue is managing people, and meaningfully punishing ne'er-do-wells.
I don't think that [nor am I inclined to think did Marx]. I think capitalism exacerbates it drastically to a markedly negative effect (though not so negative as say malevolent dictatorship). Moreover I don't perceive inequality as detrimental, it's a truism that none are equal after all.
However I do certainly have communist beliefs about the best forms for society to adopt.
In fact, imagine how far we'd be if great minds weren't restrained by having to pay rent, or work around mainstream stupidity, or having to use cheap equipment, or facing patents and other laws created to protect the captalists.
Just because we've never seen a working communist country, it doesn't mean it could never work - to think otherwise would be luddite and ignorant.