Or perhaps Darkcoin once it's made open source? (don't think it is yet...)
Darkcoin use CoinJoin method, much like Shared Coin service of Blockchain.info. We can still practice CoinJoin within Bitcoin system, therefore Darkcoin offer nothing new. CoinJoin doesn't hide your transactions completely, it just make harder to trace your money flow. With proper data mining and data analysis, your transactions might still be traced. And federal agencies have more than enough human & technology resource to do that. Zerocoin is another story, i'm excited to see what Zerocash will bring to crypto world.
Don't forget DarkSend : http://www.darkcoin.io/downloads/DarkSendDocumentation.pdf
That DarkSend function is based upon CoinJoin, i explained above. It seems that you are the one doesn't understand how DarkCoin/DarkSend work, not me.
Waw chill out I never said that you don't understand a thing ... DarkSend actually in beta 5 is in constant evolution just check the link that's all.
No matter how many beta version it have, DarkSend is still CoinJoin, nothing new.