gmrun provides a small window which lets you launch programs by typing their names. It features tab completion similar to bash or Emacs. It can complete program names from $PATH, or if the command starts with "/" it will complete file names. It provides a command history of configurable size, as well as the ability to perform forward/backward searches through the command history. gmrun was developed as a replacement for the Gnome Run program.
The Coolest DHTML Calendar is a DHTML calendar widget that works with IE >= 5.0, Mozilla, Netscape >= 6, all other Gecko-based browsers, Opera 7, Konqueror, and Safari. It comes with eight color themes, and doesn't use frames or external windows, but uses Web standards and is lightning fast. Keyboard navigation is allowed, and it can optionally show a time selector.
Xuheki is a fully featured email (IMAP) client for the Web. It looks and feels like an application rather than a Web site. It is fast, clean, and features no page reloads. It supports multiple users per installment, multiple IMAP servers per user, and multiple folders per IMAP server. It also supports text or HTML email, attachments, inline images, printing, and more. It has an "AJAX" interface that could compete with desktop-based mail user agents.