We have a guide for joining the public testnet: https://github.com/zcash/zcash/wiki/Public-Alpha-Guide
Zcash is an implementation of the "zerocash" protocol. Based on Bitcoin's code, it intends to offer a far higher standard of privacy and anonymity through a sophisticiated zero-knowledge proving scheme which preserves confidentiality of transaction metadata.
Zcash is unfinished and highly experimental. Use at your own risk.
Zcash Core is released under the terms of the MIT license. See COPYING for more information or see http://opensource.org/licenses/MIT.