Re: What happens to bitcoin when it gets as big as it can get?
The fees would be the only driving force for people to mine. If that ever happens, the miner fees would skyrocket and most likely only the miners with the best equipment can gain from it. With everyone using it, just imagine how many transactions need to be verified per second? Probably millions, and thats why miners are still important, which is why the fees would be insane. 
So the only thing that could keep it going at that point is if the UN got together and took over the mining duties. Would that keep bitcoin going without crippling fees? Or was bitcoin simply designed to fail at a certain point?