SaintSal: It's a good start but apart of semantics (icons with meaning) you also need a grammar to call it a language. In case of visual language it means that there is a way of merging simple glyphs into more complicated icon. Here is an article that describe how it can be done in medicine:

http://www.sd.polyu.edu.hk/iasdr/proceeding/papers/Collabora...

I'm looking for an open source project that I could use in my applications. There is http://thenounproject.com/ but it does not have grammar. The merging of icons is done for you (e.g., the iron icon with one, two, or three dots)