Multiple projects, one CI codebase?

[eluser]faulky[/eluser]
Hi,

I've just downloaded CI and am running through initial tutorials/HOWTO's.

Looks good, but one issue I don't seem to have a handle on yet is how to structure CI for multiple projects hosted on the same site.

For example, we have up to 5 existing applications that we might port to CI, however what would the file structure be? for example:

Example 1: Duplicating the CI codebase for each project.
=======================================================
site.root
->app1
->system
->application
->index.php
->app2
->system
->application
->index.php
->app3
->system
->application
->index.php

Example 2: Common CI codebase for all projects (my preference!)
=======================================================
site.root
->ci_system_index.php
->system
->app1
->application
->app2
->application
->app3
->application

I would like CI to work like example 2, is this feasible?

If so, what configuration files/issues would I need to be aware of?

Many thanks for any light you can shed on this for us.

Cheers, faulky.