WebIssues is a multi-platform system for issue tracking and team collaboration. It can be used to store, share, and track issues with various attributes, description, comments, and file attachments. It is easy to install and use but has many capabilities and is highly customizable. Desktop and Web clients are provided.
Wise is an experimental Web-based notebook and simple computer algebra system based on the Pure programming language. The goal is to provide a digital scratchpad that makes manipulating symbolic expressions fast, accessible, and extensible. Wise is a bottom-up approach to symbolic math written entirely in C and Python. It does not depend on any external math software or libraries (such as Maxima, Axiom, Mathematica, etc.).
Pagekite is software to make servers on "localhost" visible to the wider Internet. It can be used by Web developers to show off their works in progress to clients or colleagues, embedded developers who need direct access to devices in the field, or as an alternative to dynamic DNS for individuals/hobbyists who would rather host their own content than rely on 3rd party hosting. It creates and maintains a tunnel between your server on localhost and a remote "front-end" (a reverse proxy). Only the front-end has to have a visible IP address; the server itself can reside on a heavily firewalled computer, a mobile device, or even an anonymous node on the Tor network.