In a previous post I have tried to figure out how Idea project and modules definition files can be shared between team members considering etherogenous environments.
While I could find a few references in the Help, none of them is really describing how things should be done. I have mentioned how this can be achieved while working with Eclipse by using path variables. This same notion exists in Idea too, but I couldn’t figure out how can one can use it from the UI. But, the good news is that you can define variables to be used with modules, and also you can use variables while defining classpaths. I have figured out that by editting the .ipr file (project definition) and adding:
<UsedPathMacros>
<macro name=”MAVEN_REPO” />
</UsedPathMacros>
you will force your project to define this variable and than you can use it in both module paths and different classpaths just by specifying $MAVEN_REPO$/rest_of_path. The only thing left is to find out how you can do this without having to manually edit the .ipr and .iml files. Does anybody know the answer to this?
Disclaimer: this is the 3rd post in row about Idea and considering what may happen if Hani is picking you, I will just let everybody know that I am not associated and nor do I work for Eclipse or Idea.
mindstorms 
You may be interested in the Atlassian IDEA plugin, which allows your .ipr files to be generated from your project.xml:
http://opensource.atlassian.com/atlassian-idea-plugin/
Cheers,
Scott