[eluser]Michael Wales[/eluser]
Why would you want to transfer data from Controller to Controller - the point of the Controller is so all of your work with a particular set of data is stored within one location.
For example, a controller named users. It would have everything to do with users: register, login, logout, profiles - that is it's purpose.
Regardless, if you really wanted to do it (and break the MVC model) - store it in a DB or session.