I learned of Twine from Richard Byrne's Free Technology 4 Teachers blog post. It is great to see an opensource option that one can download and run locally or remain on the web to write.
"OpenRocket is a free, fully featured model rocket simulator that allows you to design and simulate your rockets before actually building and flying them."
"Jolicloud is super easy to install, and you've got options.
Jolicloud + Windows
Computer with Windows and Jolicloud
* Choose Windows or Jolicloud at start up
* Use your Windows files from Jolicloud
* Remove Jolicloud at any time"
OpenGoo is an Open Source Web Office. It is a complete solution for every organization to create, collaborate, share and publish all its internal and external documents.