Managing gemsets
You can not only use completely separate gemsets per application/project/etc... you can also export and load them very easily, too.
To export a gemset, assuming a project called 'albinochipmunk' running on Ruby 1.9.2:
$ rvm 1.9.2@albinochipmunk do gemset export
creates an 'albinochipmunk.gems' file.
Alternatively, if you already have a ruby selected
rvm gemset export
creates a 'default.gems' file.
You can specify the gemset filename prefix, also
rvm gemset export albinochipmunk.gems
A subtle difference with the above command is to leave off the '.gems' which will export the gems for the gemset named 'mygemsetname'
rvm gemset export albinochipmunk