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.
Hoteldruid is designed to manage weekly or daily rental of house apartments or hotel rooms. It uses a PostgreSQL, MySQL, or SQLite database as a backend. Reservations can be assigned to rooms automatically with user-defined rules. Pages with forms to check availability for Internet sites can be created. It supports multiple users with a privileges system. Documents and invoices can be printed, saved, and emailed.
Fairmat is a derivative and capital investments modelling tool. It permits you to build a pricing model for many financial projects (or derivative contracts) using a graphical representation blended with a high level algebraic language. It is also possible to use it to evaluate projects and perform real options valuations. The platform can be extended using a plug-in system.
RAPID provides stock/commodity charts, buy/sell tax accounting and trade profit graphing, plus dozens of technical analysis tools, including trendlines, point and figure, candlesticks, simple exponential and weighted moving averages, volatility, macd, stochastics, wilder DMI, standard deviation bands, trendlines, time-horizon lines, fibonacci, slope, momentum, OBV, CCI, bollinger bands, probability osc, cycle finder, derivative and integration chart, Williams Accumulation and distribution, etc.
The Open-Transactions project is a collaborative effort to develop a robust, commercial-grade, fully-featured, free-software toolkit implementing a full-strength financial cryptography library, API, CLI, and prototype server. Open-Transactions democratizes financial and monetary actions. You can use it for issuing currencies/stock, paying dividends, creating asset accounts, sending/receiving digital cash, writing/depositing cheques, cashier's cheques, creating basket currencies, trading on markets, scripting custom agreements, recurring payments, escrow, etc. Strong crypto is used. Balances are unchangeable (even by a malicious server). Receipts are destructible and redundant. The transactions are unforgeable. The cash is untraceable. The cheques are non-repudiable.
Moneychanger is a GUI built on top of Open Transactions, a financial crypto library. Moneychanger can be used to create pseudonyms, issue currencies, open accounts, withdraw and deposit cash (untraceable digital cash), write and deposit cheques, trade on markets, and much, much more.
Skrooge is a personal finances manager powered by KDE. It allows you to keep track of your expenses and income, categorize them, and build reports. You can also manage your investments and see how they perform over time. Multiple accounts are supported. Some of the features included are advanced graphical reports, tabs that help you to organize your work, infinite undo/redo (even after the file was closed), instant filtering on operations and reports, infinite category levels, mass update operations, scheduled operations, tracking of refunds, automatic processing based on search conditions, and support for multiple currencies.