eyeOS: your OS, apps and files all available through your browser
Created in August 2005, eyeOS is an open source operating system that can be installed by anyone on the web to be accessed from anywhere.
It offers many different apps, including an office suite, pdf reader, a mail application, games and much more. It is easy to install (similar to installing Wordpress) and doesn't require a database. One nice touch I noticed is that if you close your browser and get back to it, it will retain all configurations and windows positions.
eyeOS is a collaboration project that is currently spread in 9 countries with 30 languages available. It is open for anyone that wants to collaborate.
If you want to try eyeOS before installing it, you can join the 400K registered users and use the version available on their free public server. Know more about eyeOS here.;