Alpheios makes software for reading and learning languages. On any web page with Latin and ancient Greek text the user can double-click and get the definition and morphological form of any word. Support for Arabic, Chinese, and other languages are under development.
The Alpheios tools can be istalled as a Firefox extension (installation instructions here) and can be used with every Greek (in Unicode) and Latin text found online. The tools offer access to standard dictionaries, morphological analysis and much more.
Other Alpheios modules include a treebank editor, an alignment editor, text analysis, and learning management.
Videos describing the Alpheios tools are available: