Yes you can do this.
The way we do it is we have a user called "Company" that we use for all our celtralized storage. Then, we create a folder for each project that we have under that Company user. That folder is shared read/write wtih everyone in the company. This gives the abiblity for people to mount only the project folders they work on.
This also gives you the ability to e-mail
Company@domain.com and you can even setup custom filters for that user if you want to say filter by a project number in the subject field and have it automaticly put into that project folder.