People like to spout Anti-Communist rhetoric, which we've heard from and rehearsed with others. "It's great but it would never work in the real world." or "It invariably becomes corrupt." and so on. Neat little prepackaged ideas we can use whenever silly commies pop up.
In all seriousness, though, it is no less feasable than other forms of social governance. The strength of Capitalism is that it generates competition, and betterment of the few by weakening all but the best.. and as a result, the masses can share the creations of these "best". It's a very Darwinian system... however, it also results in the culture putting all its eggs in few baskets, so to speak. The majority of wealth pools in small places, like businesses and old-money families. These vast pools of money are spent on frivolous things like overpriced cars or well-tailored suits, personal jets, multiple houses, and so on... while leaving the working-class serfs to spend small ammounts of money on things which are most important to culture and society. It's an extremely competative and topheavy system, and embraces unfairness and taking financial advantage of others as a core tennant. People are encouraged to fight with one another, scrambling to be financially on top of their peers.
When we consider Communism, many of us are considering it from a standpoint of Capitalism: we see the people and the life-goals our system creates in its citizens, and we don't see how they could exist within a system which promoted unilateral cooperation, trust, and equality. However, that's what laws are for. They're like the Training Wheels someone uses when learning to ride a bike. They keep you upright, and allow you to move forward, but you are never really riding a bike at its full potential, nor are you staying upright on your own right. It takes time to realize the things you need to do in order to stay up, and to face the fear of falling down that exists in everyone. For governments, when you've learned these things, the "Training Wheels" of Law can be removed, because people realize the benefits inherint in working together as the Law dictates, pooling strength towards a common goal, and so on.
If China would get over some of their frightening policies on truth, freedom, and dogmatic nationhood, I suspect they'd be an incredibly attractive country to live in. The government is able to summon huge ammounts of resources to direct them towards things that people need, like infrastructure, high-speed trains, etc... rather than providing bait and incentives to try to convince their people to do things, as the US Government is stuck doing.
Meh, think I've rambled here, but suffice it to say that the Communist system in general is no less feasable than anything else. It is merely a different set of Laws, with a different set of challenges, with benefits unique to it. You have to be cautious about approaching it from a foriegn mindset, and try to understand it for what it is... and try not to get too caught up in rhetoric while so doing.