Bitcoin is a peer-to-peer electronic cash system that is completely decentralized, without the need for a central server or trusted parties. Users hold the crypto keys to their own money and transact directly with each other, with the help of a P2P network to check for double-spending.
siwapp is a Web application meant to help manage and create invoices in a simple, straightforward way. It can manage invoices with different serial numbers (as rectification invoices), provide printable PDF versions of the invoices with a professional look & feel, save drafts of your invoices and continue editing them later, and automatically generate invoices on a periodic basis.
P2P-Fusion is a software system that supports audiovisual creative activities and makes it easy for anyone to create, reuse, and share audio and video productions over the Internet legally, without costly servers and complicated system management. Fusion binds together a peer-to-peer network, a distributed semantic database, social enrichment features, support for embedded licenses, and a social media application toolkit into an integrated easy-to-use solution.
PyCryptoPlus is a cryptographic module similar to PyCrypto, with which it shares the API. But PyCryptoPlus is written 100% in Python, so its primary interest is educational and scientific; if you want real speed, you're better checking out PyCrypto. It was not completely written from scratch, but integrates other cipher codes when available in Python and under appropriate licenses. It contains, among other things: Block cipher algorithms (Serpent, Blowfish, Twofish, DES, 3DES, AES, Rijndael, and PRESENT); modes of operation (CMAC, ECB, CBC, CTR, and XTS); paddings (bit padding, zeros, PKCS7, PKCS12, ISO 10126, and ANSI X.923); and one-way functions (MD5, SHA1/SHA2, Whirlpool, RipeMD, RadioGatun, HMAC, and PBKDF2).
UBoat Code Navigator allows you to browse through and do manual reviews of your source code with just a Web browser. It works completely offline; there is no server or configuration required. UBoat Browse-Packs enable everybody to browse through, comment on, and review your code without any IDE, platform, or build dependencies. It lets you share your codebase with ease and also view code complexity metrics like LoC and nesting.