NetShips battle is a popular naval battle game for two players connected across the network. It provides a modular concept of three layers (network layer, game logic, and user-interface). Currently only an ncurses (console) user interface has been implemented, but adding an X11 interface or porting to MS-Windows should be easy.
S3 browser is a Web-based application for managing your files stored in Amazon S3 storage service. It supports uploading both from the server and through the browser, deleting existing files, organizing them into directories (buckets), and so on. It provides full UTF-8 support for filenames.
smtp-cli is an SMTP command line client with support for advanced features such as STARTTLS, SMTP-AUTH, or IPv6. It also has scriptable message composition capabilities supporting anything from simple plain-text messages right up to building complex HTML emails with alternative plain-text part, attachments, and inline images. It's also a convenient tool for testing and debugging SMTP servers' setups. smtp-cli can be used to check a given server's capabilities, to test your server's setup, or to create and dispatch email messages. The command line interface is intuitive, and everything is scriptable and can run in a completely non-interactive mode from scripts or cron jobs. smtp-cli is ideal for shipping log files from remote machines, running periodic mail delivery test loops, etc.